Document and Entity Information
Document and Entity Information Document - USD ($) | 12 Months Ended | ||
Dec. 31, 2018 | Jan. 31, 2019 | Jun. 30, 2018 | |
Document and Entity Information [Abstract] | |||
Entity Registrant Name | BLACK HILLS POWER INC | ||
Entity Central Index Key | 12,400 | ||
Document Type | 10-K | ||
Document Period End Date | Dec. 31, 2018 | ||
Amendment Flag | false | ||
Document Fiscal Year End Focus | 2,018 | ||
Document Fiscal Period Focus | FY | ||
Current Fiscal Year End Date | --12-31 | ||
Entity Current Reporting Status | Yes | ||
Entity Filer Category | Non-accelerated Filer | ||
Entity Common Stock Share Outstanding | 23,416,396 | ||
Entity Well-known seasoned Issuer | Yes | ||
Entity Voluntary Filers | No | ||
Entity Emerging Growth Company | false | ||
Entity Small Business | false | ||
Entity Shell Company | false | ||
Public Float | $ 0 |
Statements of Income
Statements of Income - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Income Statement [Abstract] | |||
Revenue | $ 298,080 | $ 288,433 | $ 267,632 |
Operating expenses: | |||
Fuel and purchased power | 92,886 | 87,638 | 75,026 |
Operations and maintenance | 79,523 | 74,064 | 66,384 |
Depreciation and amortization | 39,649 | 35,862 | 34,030 |
Taxes - property | 7,687 | 7,043 | 6,612 |
Total operating expenses | 219,745 | 204,607 | 182,052 |
Operating income | 78,335 | 83,826 | 85,580 |
Other income (expense): | |||
Interest expense | (22,545) | (22,421) | (22,908) |
AFUDC - borrowed | 521 | 1,137 | 1,140 |
Interest income | 676 | 904 | 1,576 |
AFUDC - equity | 221 | 2,165 | 2,165 |
Other income (expense), net | (891) | (185) | 113 |
Total other income (expense) | (22,018) | (18,400) | (17,914) |
Income before income taxes | 56,317 | 65,426 | 67,666 |
Income tax expense | (10,672) | (14,128) | (22,528) |
Net income | $ 45,645 | $ 51,298 | $ 45,138 |
Statements of Comprehensive Inc
Statements of Comprehensive Income - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Statement of Comprehensive Income [Abstract] | |||
Net income | $ 45,645 | $ 51,298 | $ 45,138 |
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, after Tax | 235 | (94) | (50) |
Other comprehensive income (loss): | |||
Other comprehensive income (loss) | 367 | 4 | 45 |
Comprehensive income | 46,012 | 51,302 | 45,183 |
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Defined Benefit Plans Adjustment | |||
Statement of Comprehensive Income [Abstract] | |||
Net income | 81 | 56 | |
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, after Tax | 81 | 56 | 53 |
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges | |||
Statement of Comprehensive Income [Abstract] | |||
Net income | 51 | 42 | |
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax | $ 51 | $ 42 | $ 42 |
Statements of Comprehensive I_2
Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Statement of Comprehensive Income [Abstract] | |||
Benefit plan liability adjustments - net gain (loss), Tax | $ 62 | $ (50) | $ (27) |
Reclassification adjustment of benefit plan liability - net gain (loss) tax | (22) | (30) | (29) |
Reclassification adjustment of cash flow hedges settled and included in net income (loss), Tax | $ (13) | $ (22) | $ (22) |
Balance Sheets
Balance Sheets - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017 |
Current assets: | ||
Cash | $ 112 | $ 16 |
Accounts receivable, net | 28,431 | 29,050 |
Accounts receivable from affiliates | 8,119 | 5,664 |
Materials, supplies and fuel | 24,853 | 23,443 |
Regulatory assets, current | 19,052 | 18,993 |
Other current assets | 4,538 | 4,724 |
Total current assets | 85,105 | 81,890 |
Investments | 4,889 | 4,926 |
Property, plant and equipment | 1,381,045 | 1,311,819 |
Less: accumulated depreciation and amortization | (376,160) | (358,946) |
Total property, plant and equipment, net | 1,004,885 | 952,873 |
Other assets: | ||
Regulatory assets, non-current | 56,680 | 59,710 |
Other assets, non-current | 9,729 | 3,747 |
Total other assets, non-current | 66,409 | 63,457 |
TOTAL ASSETS | 1,161,288 | 1,103,146 |
Current liabilities: | ||
Accounts payable | 25,122 | 14,766 |
Accounts payable to affiliates | 25,804 | 25,653 |
Accrued liabilities | 34,193 | 38,205 |
Money pool notes payable | 38,690 | 13,397 |
Regulatory liabilities, current | 2,574 | 842 |
Total current liabilities | 126,383 | 92,863 |
Long-term debt | 340,035 | 339,895 |
Deferred credits and other liabilities: | ||
Deferred income tax liabilities, net | 114,009 | 110,618 |
Regulatory liabilities, non-current | 160,642 | 148,013 |
Benefit plan liabilities | 14,606 | 16,285 |
Other, non-current liabilities | 1,368 | 1,240 |
Total deferred credits and other liabilities | 290,625 | 276,156 |
Commitments and contingencies (Notes 4, 8, 9 and 11) | ||
Stockholder’s equity: | ||
Common stock $1 par value; 50,000,000 shares authorized; 23,416,396 shares issued | 23,416 | 23,416 |
Additional paid-in capital | 39,575 | 39,575 |
Retained earnings | 342,145 | 332,499 |
Accumulated other comprehensive loss | (891) | (1,258) |
Total stockholder’s equity | 404,245 | 394,232 |
TOTAL LIABILITIES AND STOCKHOLDER’S EQUITY | $ 1,161,288 | $ 1,103,146 |
Balance Sheets (Parenthetical)
Balance Sheets (Parenthetical) - $ / shares | Dec. 31, 2018 | Dec. 31, 2017 |
Statement of Financial Position [Abstract] | ||
Common Stock, Par Value Per Share (usd per share) | $ 1 | $ 1 |
Common Stock, Shares Authorized | 50,000,000 | 50,000,000 |
Common Stock, Shares, Issued | 23,416,396 | 23,416,396 |
Statements of Cash Flows
Statements of Cash Flows - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Operating activities: | |||
Net income | $ 45,645 | $ 51,298 | $ 45,138 |
Adjustments to reconcile net income to net cash provided by operating activities - | |||
Depreciation and amortization | 39,649 | 35,862 | 34,030 |
Deferred income taxes | 5,218 | 1,004 | 20,690 |
Employee benefits | 1,518 | 817 | 1,770 |
AFUDC - equity | (221) | (2,165) | (2,165) |
Other adjustments | 2,776 | 2,429 | 391 |
Change in operating assets and liabilities - | |||
Accounts receivable and other current assets | (3,576) | 3,287 | (3,963) |
Accounts payable and other current liabilities | (5,648) | (7,254) | 6,175 |
Regulatory assets | 27 | 978 | (4,023) |
Regulatory liabilities | 2,561 | 0 | 0 |
Contributions to defined benefit pension plan | (1,795) | (4,000) | (820) |
Other operating activities | (1,407) | (1,853) | (8,339) |
Net cash provided by operating activities | 84,747 | 80,403 | 88,884 |
Investing activities: | |||
Property, plant and equipment additions | (73,456) | (79,566) | (84,750) |
Change in money pool notes receivable, net | 0 | 0 | (4,095) |
Other investing activities | (488) | (861) | (102) |
Net cash (used in) investing activities | (73,944) | (80,427) | (88,947) |
Financing activities: | |||
Change in money pool notes payable, net | (10,707) | (194) | 0 |
Net cash provided by (used in) financing activities | (10,707) | (194) | 0 |
Net change in cash | 96 | (218) | (63) |
Cash beginning of year | 16 | 234 | 297 |
Cash end of year | $ 112 | $ 16 | $ 234 |
Statements of Common Stockholde
Statements of Common Stockholder's Equity - USD ($) $ in Thousands | Total | Common Stock | Additional Paid-in Capital | Retained Earnings | Accumulated Other Comprehensive Income (Loss) |
Common Stock, Shares, Issued - Beginning Balance at Dec. 31, 2015 | 23,416,000 | ||||
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract] | |||||
Stock Issued During Period, Shares, New Issues | 0 | ||||
Common Stock, Shares, Issued - Ending Balance at Dec. 31, 2016 | 23,416,000 | ||||
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Dec. 31, 2015 | $ 23,416 | $ 39,575 | $ 330,295 | $ (1,307) | |
Stockholders' Equity Attributable to Parent [Abstract] | |||||
Stock Issued During Period, Value, New Issues | 0 | 0 | |||
Net income | $ 45,138 | 45,138 | |||
Non-cash Dividend to Parent Company | (52,500) | ||||
Other adjustments | 0 | ||||
Other Comprehensive Income (Loss), Net of Tax | 45 | 45 | |||
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Dec. 31, 2016 | $ 384,662 | $ 23,416 | 39,575 | 322,933 | (1,262) |
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract] | |||||
Stock Issued During Period, Shares, New Issues | 0 | ||||
Common Stock, Shares, Issued - Ending Balance at Dec. 31, 2017 | 23,416,396 | 23,416,000 | |||
Stockholders' Equity Attributable to Parent [Abstract] | |||||
Stock Issued During Period, Value, New Issues | $ 0 | 0 | |||
Net income | $ 51,298 | 51,298 | |||
Non-cash Dividend to Parent Company | (42,000) | ||||
Other adjustments | 268 | ||||
Other Comprehensive Income (Loss), Net of Tax | 4 | 4 | |||
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Dec. 31, 2017 | $ 394,232 | $ 23,416 | 39,575 | 332,499 | (1,258) |
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract] | |||||
Stock Issued During Period, Shares, New Issues | 0 | ||||
Common Stock, Shares, Issued - Ending Balance at Dec. 31, 2018 | 23,416,396 | 23,416,000 | |||
Stockholders' Equity Attributable to Parent [Abstract] | |||||
Stock Issued During Period, Value, New Issues | $ 0 | 0 | |||
Net income | $ 45,645 | 45,645 | |||
Non-cash Dividend to Parent Company | (36,000) | ||||
Other adjustments | 1 | ||||
Other Comprehensive Income (Loss), Net of Tax | 367 | 367 | |||
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest at Dec. 31, 2018 | $ 404,245 | $ 23,416 | $ 39,575 | $ 342,145 | $ (891) |
Business Description and Summar
Business Description and Summary of Significant Accounting Policies | 12 Months Ended |
Dec. 31, 2018 | |
Organization, Consolidation and Presentation of Financial Statements [Abstract] | |
Business Description and Summary of Significant Accounting Policies | BUSINESS DESCRIPTION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Business Description Black Hills Power, Inc., doing business as South Dakota Electric (the “Company”, “we”, “us” or “our”) is a regulated electric utility serving customers in South Dakota, Wyoming and Montana. We are a wholly-owned subsidiary of BHC or the Parent, a public registrant listed on the New York Stock Exchange. Basis of Presentation The financial statements include the accounts of Black Hills Power, Inc. and also our ownership interests in the assets, liabilities and expenses of our jointly owned facilities (Note 3 ) and are prepared in accordance with GAAP. Use of Estimates and Basis of Presentation The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Changes in facts and circumstances or additional information may result in revised estimates and actual results could differ materially from those estimates. Cash Equivalents We consider all highly liquid investments with an original maturity of three months or less to be cash equivalents. As of December 31, 2018 and 2017, we have no cash equivalents. Regulatory Accounting Our regulated electric operations are subject to regulation by various state and federal agencies. The accounting policies followed are generally subject to the Uniform System of Accounts of FERC. If rate recovery becomes unlikely or uncertain due to competition or regulatory action, these accounting standards may no longer apply which could require these net regulatory assets to be charged to current income or OCI. Our regulatory assets represent amounts for which we will recover the cost, but generally are not allowed a return, except as described below. In the event we determine that our regulated net assets no longer meet the criteria for accounting standards for regulated operations, the accounting impact to us could be an extraordinary non-cash charge to operations, which could be material. We had the following regulatory assets and liabilities as of December 31 (in thousands): 2018 2017 Regulatory assets Loss on reacquired debt (a) $ 1,259 $ 1,534 Deferred taxes on AFUDC (b) 5,020 5,095 Employee benefit plans and related deferred taxes (c) 19,868 19,465 Deferred energy and fuel cost adjustments (a) 20,334 19,602 Deferred taxes on flow through accounting (c) 8,749 7,579 Decommissioning costs (b) 8,196 10,252 Vegetation management (a) 10,366 12,669 Other regulatory assets (a) 1,940 2,507 $ 75,732 $ 78,703 Less current regulatory assets (19,052 ) (18,993 ) Regulatory assets, non-current $ 56,680 $ 59,710 Regulatory liabilities Cost of removal for utility plant (a) $ 52,366 $ 44,056 Employee benefit plans and related deferred taxes (c) 7,518 6,808 Excess deferred income taxes (c) 100,276 97,101 TCJA revenue reserve 2,523 — Other regulatory liabilities (c) 533 890 $ 163,216 $ 148,855 Less current regulatory liabilities (2,574 ) (842 ) Regulatory liabilities, non-current $ 160,642 $ 148,013 ____________________ (a) We are allowed a recovery of costs but we are not allowed a rate of return. (b) In addition to recovery of costs, we are allowed a rate of return. (c) In addition to recovery or repayment of costs, we are allowed a return on a portion of this amount or a reduction in rate base. Regulatory assets represent items we expect to recover from customers through probable future increases in rates. Loss on Reacquired Debt - The early redemption premium on reacquired debt is being amortized over the remaining term of the original bonds. Deferred Taxes on AFUDC - The equity component of AFUDC is considered a permanent difference for tax purposes with the tax benefit being flowed through to customers as prescribed or allowed by regulators. If, based on a regulator’s action, it is probable the utility will recover the future increase in taxes payable represented by this flow-through treatment through a rate revenue increase, a regulatory asset is recognized. This regulatory asset itself is a temporary difference for which a deferred tax liability must be recognized. Accounting standards for income taxes specifically address AFUDC-equity, and require a gross-up of such amounts to reflect the revenue requirement associated with a rate-regulated environment. Employee Benefit Plans - Employee benefit plans include the unrecognized prior service costs and net actuarial loss associated with our defined benefit pension plan and other post-retirement benefit plans in regulatory assets rather than in accumulated other comprehensive income. In addition, this regulatory asset includes the income tax effect of the adjustment required under accounting for compensation-defined benefit plans to record the full pension and post-retirement benefit obligations. Such amounts have been grossed-up to reflect the revenue requirement associated with a rate regulated environment. Deferred Energy and Fuel Cost Adjustments - Deferred energy and fuel cost adjustments represent the cost of electricity delivered to our customers that is either higher or lower than the current rates and will be recovered or refunded in future rates. Deferred energy and fuel cost adjustments are recorded and recovered or amortized as approved by the appropriate state commission. We file periodic quarterly, semi-annual and/or annual filings to recover these costs based on the respective cost mechanisms approved by the applicable state utility commissions. Deferred Taxes on Flow-Through Accounting - Under flow-through accounting, the income tax effects of certain tax items are reflected in our cost of service for the customer in the year in which the tax benefits are realized and result in lower utility rates. A regulatory asset was established to reflect that future increases in income taxes payable will be recovered from customers as the temporary differences reverse. As a result of this regulatory treatment, we continue to record a tax benefit for costs considered currently deductible for tax purposes, but are capitalized for book purposes. Decommissioning Costs - We received approval in 2014 for regulatory treatment on the remaining net book values and decommissioning costs of our decommissioned coal plants. Vegetation Management Costs - We received approval in 2013 for regulatory treatment on vegetation management maintenance costs for our distribution system rights-of-way. Regulatory liabilities represent items we expect to refund to customers through probable future decreases in rates. Cost of Removal for Utility Plant - Cost of removal for utility plant represents the estimated cumulative net provisions for future removal costs included in depreciation expense for which there is no legal obligation for removal. Employee Benefit Plans - Employee benefit plans represent the cumulative excess of pension and other postretirement benefit costs recovered in rates over pension expense recorded in accordance with accounting standards for compensation-retirement benefits. In addition, this regulatory liability includes the income tax effect of the adjustment required under accounting for compensation-defined benefit plans, to record the full pension and post-retirement benefit obligations. Such income tax effect has been grossed-up to account for the revenue requirement associated with a rate regulated environment. Excess Deferred Income Taxes - The revaluation of our deferred tax assets and liabilities due to the passage of the TCJA is recorded as an excess deferred income tax to be refunded to customers primarily using the normalization principles as prescribed in the TCJA. See additional details below. TCJA Revenue Reserve - Revenue subject to refund at December 31, 2018, represents revenue reserved as a result of the TCJA. See below “ TCJA Revenue Reserve ” under Revenue recognition for further disclosure. Excess Deferred Income Taxes As of December 31, 2018 and 2017 , we have a regulatory liability associated with TCJA related items of approximately $100 million and $97 million , respectively. The majority of this regulatory liability relates to excess deferred taxes resulting from the remeasurement of deferred tax assets and liabilities in 2017. A significant portion of the excess deferred taxes are subject to the average rate assumption method, as prescribed by the IRS, and will generally be amortized as a reduction of customer rates over the remaining lives of the related assets. As of December 31, 2018, the Company has amortized $0.9 million of this regulatory liability. The portion that was eligible for amortization under the average rate assumption method in 2018, but is awaiting resolution of the treatment of these amounts in future regulatory proceedings, has not been recognized and may be refunded in customer rates at any time in accordance with the resolution of pending or future regulatory proceedings. See Note 6 for more information. Accounts Receivable and Allowance for Doubtful Accounts Accounts receivable consists of sales to residential, commercial, industrial, municipal and other customers all of which do not bear interest. These accounts receivable are stated at billed and unbilled amounts, net of write-offs or payment received. We maintain an allowance for doubtful accounts which reflects our best estimate of uncollectible trade receivables. We regularly review our trade receivable allowances by considering such factors as historical experience, credit worthiness, the age of the receivable balances and current economic conditions that may affect collectibility. In specific cases where we are aware of a customer’s inability or reluctance to pay, we record an allowance for doubtful accounts to reduce the net receivable balance to the amount we reasonably expect to collect. However, if circumstances change, our estimate of the recoverability of accounts receivable could be affected. Circumstances which could affect our estimates include, but are not limited to, customer credit issues, the level of commodity prices, customer deposits and general economic conditions. Accounts are written off once they are deemed to be uncollectible or the time allowed for dispute under the contract has expired. Following is a summary of accounts receivable as of December 31 (in thousands): 2018 2017 Accounts receivable, trade $ 16,236 $ 15,994 Unbilled revenue 12,333 13,280 Less Allowance for doubtful accounts (138 ) (224 ) Accounts receivable, net $ 28,431 $ 29,050 Changes to allowance for doubtful accounts for the years ended December 31, were as follows (in thousands): Balance at beginning of year Additions charged to costs and expenses Deductions charged to costs and expenses Balance at end of year 2018 $ 224 $ 911 $ (997 ) $ 138 2017 $ 157 $ 882 $ (815 ) $ 224 2016 $ 207 $ 644 $ (694 ) $ 157 Revenue Recognition Revenues are recognized in an amount that reflects the consideration we expect to receive in exchange for goods or services, when control of the promised goods or services is transferred to our customers. Our primary types of revenue contracts are: • Regulated electric utility services tariffs - Our regulated operations, as defined by ASC 980, provide services to regulated customers under rates, charges, terms and conditions of service, and prices determined by the jurisdictional regulators designated for our service territories. Collectively, these rates, charges, terms and conditions are included in a tariff, which governs all aspects of the provision of our regulated services. Our regulated services primarily encompass single performance obligations material to the context of the contract for delivery of commodity electricity and electric transmission services. These service revenues are variable based on quantities delivered, influenced by seasonal business and weather patterns. Tariffs are only permitted to be changed through a rate-setting process involving the regulator-empowered statute to establish contractual rates between the utility and its customers. All of our regulated utility sales are subject to regulatory-approved tariffs. • Power sales agreements - We have long-term wholesale power sales agreements with other load serving entities, including affiliates, for the sale of excess power from owned generating units. These agreements include a combination of “take or pay” arrangements, where the customer is obligated to pay for the energy regardless of whether it actually takes delivery, as well as “requirements only” arrangements, where the customer is only obligated to pay for the energy the customer needs. In addition to these long-term contracts, the Company also sells excess energy to other load-serving entities on a short-term basis. The pricing for all of these arrangements is included in the executed contracts or confirmations, reflecting the standalone selling price, and is variable based on energy delivered. The following table depicts the disaggregation of revenue, including intercompany revenue, from contracts with customers by customer type and timing of revenue recognition. Sales tax and other similar taxes are excluded from revenues. Year ended December 31, 2018 (in thousands) Customer types: Retail $ 197,184 Wholesale 33,687 Market - off-system sales 17,691 Transmission/Other 49,015 Revenue from contracts with customers 297,577 Other revenues 503 Total revenues $ 298,080 Timing of revenue recognition: Services transferred over time $ 297,577 Revenue from contracts with customers $ 297,577 The majority of the our revenue contracts are based on variable quantities delivered; any fixed consideration contracts with an expected duration of one year or more are immaterial to our revenues. Variable consideration constraints in the form of discounts, rebates, credits, price concessions, incentives, performance bonuses, penalties or other similar items are not material for our revenue contracts. We are the principal in our revenue contracts, as we have control over the services prior to those services being transferred to the customer. Revenue Not in Scope of ASC 606 Other revenues included in the table above include revenue accounted for under separate accounting guidance, including alternative revenue programs revenue under ASC 980. Significant Judgments and Estimates TCJA revenue reserve The TCJA or “tax reform”, signed into law on December 22, 2017, reduced the federal corporate income tax rate from 35% to 21% effective for tax years beginning after December 31, 2017. We have been collaborating with our regulators in the states in which we provide utility service to deliver to customers the benefits of a lower corporate federal income tax rate beginning in 2018 with the passage of the TCJA. We estimated and recorded a revenue reserve of approximately $10 million during the year ended December 31, 2018. On September 4, 2018, the SDPUC approved a settlement agreement for South Dakota Electric allowing the Company to pass on the benefits of a lower corporate federal income tax rate to our South Dakota retail customers. As of December 31, 2018, approximately $7.6 million has been delivered to customers and approximately $2.5 million remains in reserve. Unbilled Revenue To the extent that deliveries have occurred but a bill has not been issued, the Company accrues an estimate of the revenue since the latest billing. This estimate is calculated based on several factors including billings through the last billing cycle in a month and prices in effect in our jurisdictions. Each month the estimated unbilled revenue amounts are trued-up and recorded in Accounts receivable, net on the accompanying Balance Sheets. Contract Balances The nature of our primary revenue contracts provides an unconditional right to consideration upon service delivery; therefore, no customer contract assets or liabilities exist. The unconditional right to consideration is represented by the balance in our Accounts Receivable and is further discussed above. We do not typically incur costs that would be capitalized, to obtain or fulfill a contract. Practical Expedients Our revenue contracts generally provide for performance obligations that are fulfilled and transfer control to customers over time, represent a series of distinct services that are substantially the same, involve the same pattern of transfer to the customer, and provide a right to consideration from our customers in an amount that corresponds directly with the value to the customer for the performance completed to date. Therefore, we recognize revenue in the amount to which we have a right to invoice. We have revenue contract performance obligations with similar characteristics, and we reasonably expect that the financial statement impact of applying the new revenue recognition guidance to a portfolio of contracts would not differ materially from applying this guidance to the individual contracts or performance obligations within the portfolio. Therefore, we have elected the portfolio approach in applying the new revenue guidance. Materials, Supplies and Fuel Materials, supplies and fuel used for construction, operation and maintenance purposes are recorded using the weighted-average cost method. Deferred Financing Costs Deferred financing costs are amortized over the estimated useful life of the related debt. Deferred financing costs are presented on the balance sheet as an adjustment to the related debt liabilities. Property, Plant and Equipment Additions to property, plant and equipment are recorded at cost. Included in the cost of regulated construction projects is AFUDC, when applicable, which represents the approximate composite cost of borrowed funds and a return on equity used to finance a regulated utility project. We also capitalize interest, when applicable, on undeveloped leasehold costs and certain non-regulated construction projects. In addition, asset retirement costs associated with tangible long-lived regulated utility assets are recognized as liabilities with an increase to the carrying amounts of the related long-lived regulated utility assets in the period incurred. The amounts capitalized are included in Property, plant and equipment on the accompanying Balance Sheets. The cost of regulated utility property, plant and equipment retired, or otherwise disposed of in the ordinary course of business, less salvage plus retirement costs, is charged to accumulated depreciation. Estimated removal costs associated with non-legal retirement obligations related to our regulated electric properties are reclassified from accumulated depreciation and reflected as regulatory liabilities. Ordinary repairs and maintenance of property, except as allowed under rate regulations, are charged to operations as incurred. Property, plant and equipment is tested for impairment when it is determined that the carrying value of the assets may not be recoverable. A loss is recognized in the current period if it becomes probable that part of a cost of a plant under construction or recently completed plant will be disallowed for recovery from customers and a reasonable estimate of the disallowance can be made. For investments in property, plant and equipment that are abandoned and not expected to go into service, incurred costs and related deferred tax amounts are compared to the discounted estimated future rate recovery, and a loss is recognized, if necessary. Depreciation provisions for regulated electric property, plant and equipment are computed on a straight-line basis using an annual composite rate of 2.3% in 2018 , 2.1% in 2017 and 2.2% in 2016 . Accrued Liabilities The following amounts by major classification are included in Accrued liabilities on the accompanying Balance Sheets as of December 31 (in thousands): 2018 2017 Accrued employee compensation, benefits and withholdings $ 4,206 $ 4,305 Accrued property taxes 6,332 5,930 Accrued income taxes 12,536 17,472 Customer deposits and prepayments 5,204 4,863 Accrued interest 4,627 4,708 Other (none of which is individually significant) 1,288 927 Total accrued liabilities $ 34,193 $ 38,205 Derivatives and Hedging Activities The accounting standards for derivatives and hedging require that derivative instruments be recorded on the balance sheet as either an asset or liability measured at its fair value and changes in the derivative instruments be recognized in earnings unless specific hedge accounting criteria are met and designated accordingly, including the normal purchase and normal sales exception. Changes in the fair value for derivative instruments that do not meet this exception are recognized in the income statement as they occur. From time to time we utilize risk management contracts including interest rate swaps to fix the interest on variable rate debt, or to lock in the Treasury yield component associated with anticipated issuance of senior notes. For swaps that settled in connection with the issuance of senior debt, the effective portion is deferred as a component in AOCI and recognized as interest expense over the life of the senior note. As of December 31, 2018, we have no outstanding interest rate swap agreements. Revenues and expenses on contracts that qualify as derivatives may be elected to be accounted for under the normal purchases and normal sales exception and are recognized when the underlying physical transaction is completed under the accrual basis of accounting. Normal purchases and normal sales are contracts where physical delivery is probable, quantities are expected to be used or sold in the normal course of business over a reasonable amount of time, and price is not tied to an unrelated underlying derivative. As part of our regulated electric operations, we enter into contracts to buy and sell energy to meet the requirements of our customers. These contracts include short-term and long-term commitments to purchase and sell energy in the retail and wholesale markets with the intent and ability to deliver or take delivery. If it was determined that a transaction designated as a normal purchase or normal sale no longer met the exception, the fair value of the related contract would be reflected as either an asset or liability, under the accounting standards for derivatives and hedging. Fair Value Measurements We use the following fair value hierarchy for determining inputs for our financial instruments. Our financial instruments’ assets and liabilities for financial instruments are classified and disclosed in one of the following fair value categories: Level 1 — Unadjusted quoted prices available in active markets that are accessible at the measurement date for identical unrestricted assets or liabilities. Level 1 instruments primarily consist of highly liquid and actively traded financial instruments with quoted pricing information on an ongoing basis. Level 2 — Pricing inputs include quoted prices for identical or similar assets and liabilities in active markets other than quoted prices in Level 1, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability and inputs that are derived principally from or corroborated by observable market data by correlation or other means. Level 3 — Pricing inputs are generally less observable from objective sources. These inputs reflect management’s best estimate of fair value using its own assumptions a market participant would use in pricing the asset or liability. Assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. Our assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the placement within the fair value hierarchy levels. We record transfers, if necessary, between levels at the end of the reporting period for all of our financial instruments. Transfers into Level 3, if any, occur when significant inputs used to value the derivative instruments become less observable such as a significant decrease in the frequency and volume in which the instrument is traded, negatively impacting the availability of observable pricing inputs. Transfers out of Level 3, if any, occur when the significant inputs become more observable such as the time between the valuation date and the delivery date of a transaction becomes shorter, positively impacting the availability of observable pricing inputs. We currently do not have any Level 3 investments. Income Taxes We file a federal income tax return with other members of the Parent’s consolidated group. For financial statement purposes, federal income taxes are allocated to the individual companies based on amounts calculated on a separate return basis. The Company uses the asset and liability method in accounting for income taxes. Under the asset and liability method, deferred income taxes are recognized at currently enacted income tax rates, to reflect the tax effect of temporary differences between the financial and tax basis of assets and liabilities as well as operating loss and tax credit carryforwards. Such temporary differences are the result of provisions in the income tax law that either require or permit certain items to be reported on the income tax return in a different period than they are reported in the financial statements. On December 22, 2017, the U.S. government enacted comprehensive tax legislation commonly referred to as the TCJA. The TCJA makes broad and complex changes to the U.S. tax code, including, but not limited to reducing the U.S. federal corporate tax rate from 35% to 21% . We use the deferral method of accounting for investment tax credits as allowed by our rate-regulated jurisdictions. Such a method results in the investment tax credit being amortized as a reduction to income tax expense over the estimated useful lives of the underlying property that gave rise to the credit. We recognize interest income or interest expense and penalties related to income tax matters in Income tax (expense) benefit on the Statements of Income. We account for uncertainty in income taxes recognized in the financial statements in accordance with the accounting standards for income taxes. The unrecognized tax benefit is classified in Other, non-current liabilities on the accompanying Balance Sheets. See Note 6 for additional information. Recently Issued Accounting Standards Leases, ASU 2016-02 In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , which supersedes ASC 840, Leases. This ASU requires lessees to recognize a right-of-use asset and lease liability on the balance sheet for most leases, whereas today only financing-type lease liabilities (capital leases) are recognized on the balance sheet. In addition, the definition of a lease has been revised in regards to when an arrangement conveys the right to control the use of the identified asset under the arrangement which may result in changes to the classification of an arrangement as a lease. The ASU does not significantly change the lessees’ recognition, measurement and presentation of expenses and cash flows from the previous accounting standard. Lessors’ accounting under the ASU is largely unchanged from the previous accounting standard. The ASU expands the disclosure requirements of lease arrangements. Under the original guidance, lessees and lessors will use a modified retrospective transition approach, which requires application of the new guidance at the beginning of the earliest comparative period presented in the year of adoption. The guidance is effective for interim and annual reporting periods beginning after December 15, 2018, with early adoption permitted. In January 2018, the FASB issued amendments to the new lease standard, ASU No. 2018-01, allowing an entity to elect not to assess whether certain land easements are, or contain, leases when transitioning to the new lease standard. The FASB also issued additional amendments to the new lease standard in July 2018, ASU No. 2018-11, allowing companies to adopt the new standard with a cumulative effect adjustment as of the beginning of the year of adoption with prior year comparative financial information and disclosures remaining as previously reported. We adopted this standard on January 1, 2019. For existing or expired land easements that were not previously accounted for as a lease, we elected the practical expedient which provides for no assessment of these easements. Further, we adopted the new standard with a cumulative effect adjustment with prior year comparative financial information remaining as previously reported when transitioning to the new standard. The standard also provides a transition practical expedient, commonly referred to as the “package of three”, that must be taken together and allows entities to (1) not reassess whether existing contracts contain leases, (2) carryforward the existing lease classification, and (3) not reassess initial direct costs associated with existing leases. We elected the “package of three” practical expedient. We have implemented a new lease accounting system and adjusted related procedures and controls accordingly. We will record an operating lease right of use asset and an off-setting operating lease obligation liability as of January 1, 2019 for approximately $14 million , respectively, primarily driven by the intercompany ground lease with WRDC for Wygen III. Adoption of this standard did not have a material impact on our financial position, results of operations or cash flows. Recently Adopted Accounting Standards Revenue from Contracts with Customers, ASU 2014-09 Effective January 1, 2018, we adopted ASU 2014-09, Revenue from Contracts with Customers (Topic 606) , and its related amendments (collectively known as ASC 606). Under this standard, revenue is recognized when a customer obtains control of promised goods or services in an amount that reflects the consideration the entity expects to receive in exchange for those goods or services. In addition, the standard requires disclosure of the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. We applied the five-step method outlined in the ASU to all in-scope revenue streams and elected the modified retrospective implementation method. Implementation of the standard did not have a material impact on our financial position, results of operations or cash flows. Implementation of the standard did not have a significant impact on the measurement or recognition of revenue; therefore, no cumulative adoption adjustment to the opening balance of Retained earnings at the date of initial application was necessary. The additional disclosures required by the ASU are included in Note 1. Compensation - Retirement Benefits: Improving the Presentation of Net Periodic Pension Cost and Net Periodic Post-Retirement Benefit Cost, ASU 2017-07 Effective January 1, 2018, we adopted ASU 2017-07, Compensation – Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Post-Retirement Benefit Cost . The standard requires employers to report the service cost component in the same line item(s) as other compensation costs, and requires the other components of net periodic pension and post-retirement benefit costs to be separately presented in the income statement outside of income from operations. Additionally, only the service cost component may be eligible for capitalization, when applicable. However, all cost components remain eligible for capitalization under FERC regulations. The capitalization of only the service cost component of net periodic pension and post-retirement benefit costs in assets was applied on a prospective basis for the year ended December 31, 2018. Retrospective impact was not material and therefore not adjusted. For our rate-regulated entities, we capitalize the other components of net periodic benefit costs into regulatory assets or regulatory liabilities and maintain a FERC-to-GAAP reporting difference for these capitalized costs. The presentation changes required for net periodic pension and post-retirement costs resulted in offsetting changes to Operating income and Other income. Implementation of the standard did not have a material impact on our financial position, results of operations or cash flows. Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments, AS |
Property, Plant and Equipment
Property, Plant and Equipment | 12 Months Ended |
Dec. 31, 2018 | |
Property, Plant and Equipment [Abstract] | |
Property, Plant and Equipment | PROPERTY, PLANT AND EQUIPMENT Property, plant and equipment at December 31 consisted of the following (dollars in thousands): 2018 2017 Weighted Weighted Average Average 2018 Useful Life (in years) 2017 Useful Life (in years) Electric plant: Production $ 588,565 46 $ 587,323 46 Transmission 208,610 48 186,045 49 Distribution 394,475 45 375,214 46 Plant acquisition adjustment (a) 4,870 32 4,870 32 General 154,621 28 153,535 32 Total plant-in-service 1,351,141 1,306,987 Construction work in progress 29,904 4,832 Total electric plant 1,381,045 1,311,819 Less accumulated depreciation and amortization (376,160 ) (358,946 ) Electric plant net of accumulated depreciation and amortization $ 1,004,885 $ 952,873 __________________ (a) The plant acquisition adjustment is included in rate base and is being recovered with 12 years remaining. |
Jointly Owned Facilities
Jointly Owned Facilities | 12 Months Ended |
Dec. 31, 2018 | |
Jointly Owned Utility Plant, Net Ownership Amount [Abstract] | |
Jointly Owned Facilities | JOINTLY OWNED FACILITIES Our financial statements include our share of several jointly-owned utility facilities as described below. Our share of the facilities’ expenses are reflected in the appropriate categories of operating expenses in the Statements of Income (Loss). Each owner of the facility is responsible for financing its investment in the jointly-owned facilities. • We own a 20% interest in the Wyodak Plant (the “Plant”), a coal-fired electric generating station located in Campbell County, Wyoming. PacifiCorp owns the remaining ownership percentage and is the operator of the Plant. We receive our proportionate share of the Plant’s capacity and are committed to pay our share of its additions, replacements and operating and maintenance expenses. • We own a 35% interest in, and are the operator of, the Converter Station Site and South Rapid City Interconnection (the transmission tie), an AC-DC-AC transmission tie. Basin Electric owns the remaining ownership percentage. The transmission tie provides an interconnection between the Western and Eastern transmission grids, which provides us with access to both the WECC region and the SPP region. The total transfer capacity of the transmission tie is 400 MW, including 200 MW West to East and 200 MW from East to West. We are committed to pay our proportionate share of the additions, replacements and operating and maintenance expenses. • We own a 52% interest in the Wygen III power plant. MDU and the City of Gillette each owns an undivided ownership interest in Wygen III and are obligated to make payments for costs associated with administrative services and a proportionate share of the costs of operating the plant for the life of the facility. We retain responsibility for plant operations. • We own 55 MW of Cheyenne Prairie, a 95 MW gas-fired power generation facility located in Cheyenne, Wyoming. Wyoming Electric owns the remaining 40 MW. We are committed to pay our proportionate share of the additions, replacements and operating and maintenance expenses. As of December 31, 2018 , our interests in jointly-owned generating facilities and transmission systems were (in thousands): Interest in jointly-owned facilities Plant in Service Construction Work in Progress Accumulated Depreciation Wyodak Plant $ 115,198 $ 384 $ 61,730 Transmission Tie $ 20,855 $ 1,860 $ 6,667 Wygen III $ 140,072 $ 645 $ 22,647 Cheyenne Prairie $ 92,053 $ 69 $ 11,460 |
Long term Debt
Long term Debt | 12 Months Ended |
Dec. 31, 2018 | |
Long-term Debt, Unclassified [Abstract] | |
Long-term Debt | LONG-TERM DEBT Long-term debt outstanding at December 31 was as follows (in thousands): Interest Rate at Balance Outstanding Due Date December 31, 2018 December 31, 2018 December 31, 2017 First Mortgage Bonds due 2032 August 15, 2032 7.23 % 75,000 75,000 First Mortgage Bonds due 2039 November 1, 2039 6.13 % 180,000 180,000 First Mortgage Bonds due 2044 October 20, 2044 4.43 % 85,000 85,000 Less unamortized debt discount (86 ) (90 ) Series 94A Debt (a) June 1, 2024 1.93 % 2,855 2,855 Less unamortized deferred financing costs (2,734 ) (2,870 ) Long-term Debt 340,035 339,895 ___________________ (a) Variable interest rate at December 31, 2018 . Net deferred financing costs of approximately $2.7 million and $2.9 million were recorded on the accompanying Balance Sheets in long-term debt at December 31, 2018 and 2017 , respectively, and are being amortized over the term of the debt. Amortization of deferred financing costs of approximately $0.1 million for each of the years ended December 31, 2018 , 2017 and 2016 are included in Interest expense on the accompanying Statements of Income. Substantially all of our property is subject to the lien of the indenture securing our first mortgage bonds. First mortgage bonds may be issued in amounts limited by property, earnings and other provisions of the mortgage indentures. We were in compliance with our debt covenants at December 31, 2018 . Long-term Debt Maturities Scheduled maturities of our outstanding long-term debt (excluding unamortized discounts and unamortized deferred financing costs) are as follows (in thousands): 2019 $ — 2020 $ — 2021 $ — 2022 $ — 2023 $ — Thereafter $ 342,855 |
Fair Value of Financial Instrum
Fair Value of Financial Instruments: Fair Value of Financial Instruments | 12 Months Ended |
Dec. 31, 2018 | |
Fair Value Disclosures [Abstract] | |
Fair Value of Financial Instruments | FAIR VALUE OF FINANCIAL INSTRUMENTS The estimated fair values of our financial instruments at December 31 were as follows (in thousands): 2018 2017 Carrying Value Fair Value Carrying Value Fair Value Cash (a) $ 112 $ 112 $ 16 $ 16 Long-term debt (b) (c) $ 340,035 $ 412,894 $ 339,895 $ 446,978 _______________ (a) The cash fair value approximates carrying value and therefore is classified as Level 1 in the fair value hierarchy. We believe that the market risk arising from cash in a bank account is minimal. (b) Long-term debt is valued based on observable inputs available either directly or indirectly for similar liabilities in active markets and therefore is classified in Level 2 in the fair value hierarchy. (c) Carrying amount of long-term debt is net of deferred financing costs. The following methods and assumptions were used to estimate the fair value of each class of our financial instruments. Long-Term Debt For additional information on our long-term debt, see Note 4 . |
Income Taxes
Income Taxes | 12 Months Ended |
Dec. 31, 2018 | |
Income Tax Disclosure [Abstract] | |
Income Taxes | INCOME TAXES On December 22, 2017, the U.S. government enacted comprehensive tax legislation commonly referred to as the TCJA. The TCJA reduced the U.S. federal corporate tax rate from 35% to 21% . As such, the Company has remeasured the deferred income taxes at the 21% federal tax rate as of December 31, 2017. As a result of the revaluation at December 31, 2017, deferred tax assets and liabilities were reduced by approximately $103 million . Of the $103 million , approximately $97 million was reclassified to a regulatory liability. As of December 31, 2018 we have a regulatory liability associated with TCJA related items of $100 million . A significant portion of the excess deferred taxes are subject to the average rate assumption method, as prescribed by the IRS, and will generally be amortized as a reduction of customer rates over the remaining lives of the related assets. As of December 31, 2018, the Company has amortized $0.9 million of this regulatory liability. The portion that was eligible for amortization under the average rate assumption method in 2018, but is awaiting resolution of the treatment of these amounts in future regulatory proceedings, has not been recognized and may be refunded in customer rates at any time in accordance with the resolution of pending or future regulatory proceedings. Income tax expense for the years ended December 31 was as follows (in thousands): 2018 2017 2016 Current: Federal $ 5,454 $ 13,124 $ 1,838 Deferred: Federal 5,958 1,004 20,690 Excess deferred tax amortization (740 ) — — $ 5,218 $ 1,004 $ 20,690 Total income tax expense $ 10,672 $ 14,128 $ 22,528 The temporary differences, which gave rise to the net deferred tax liability, for the years ended December 31 were as follows (in thousands): 2018 2017 Deferred tax assets: Employee benefits $ 2,404 $ 3,012 Regulatory liabilities 25,587 24,984 Other 2,317 1,678 Total deferred tax assets 30,308 29,674 Deferred tax liabilities: Accelerated depreciation and other plant related differences (125,594 ) (122,002 ) Regulatory assets (7,147 ) (7,008 ) Employee benefits (2,719 ) (2,595 ) Deferred costs (8,572 ) (8,447 ) Other (285 ) (240 ) Total deferred tax liabilities (144,317 ) (140,292 ) Net deferred tax liability $ (114,009 ) $ (110,618 ) The effective tax rate differs from the federal statutory rate for the years ended December 31, as follows: 2018 2017 2016 Federal statutory rate 21.0% 35.0% 35.0% Amortization of excess deferred and investment tax credits (1.3) (0.1) (0.4) AFUDC Equity 0.1 (1.0) (0.9) Flow-through adjustments (a) (1.7) (1.8) (0.9) Tax credits — — (0.1) TCJA corporate rate reduction (b) 2.5 (9.2) — Other (1.7) (1.3) 0.6 18.9% 21.6% 33.3% _________________________ (a) Flow-through adjustments related primarily to an accounting method change for tax purposes that allows us to take a current tax deduction for repair costs. We recorded a deferred income tax liability in recognition of the temporary difference created between book and tax treatment and we flowed the tax benefit through to tax expense. (b) On December 22, 2017, the TCJA was signed into law reducing the federal corporate rate from 35% to 21% , effective January 1, 2018. The 2017 effective tax rate reduction reflects the revaluation of deferred income taxes required by the change. During the year ended December 31, 2018, we recorded approximately $0.9 million of additional tax expense associated with changes in the prior estimated impacts of TCJA related items. The following table reconciles the total amounts of unrecognized tax benefits, without interest, included in Other deferred credits and other liabilities on the accompanying Balance Sheet (in thousands): 2018 2017 Unrecognized tax benefits at January 1 $ 302 $ 493 Additions for current year tax positions — 13 Additions for prior year tax positions 2 — Reductions for prior year tax positions (55 ) (204 ) Unrecognized tax benefits at December 31 $ 249 $ 302 The total amount of unrecognized tax benefits that, if recognized, would impact the effective tax rate is not material to the financial results of the Company. It is the Company’s continuing practice to recognize interest and/or penalties related to income tax matters in income tax expense. During the years ended December 31, 2018 and 2017 , the interest expense recognized was not material to the financial results of the Company. We do not anticipate that total unrecognized tax benefits will significantly change due to the settlement of any audits or the expiration of statutes of limitations on or before December 31, 2019 . We file income tax returns in the United States federal jurisdictions as a member of the BHC consolidated group. |
Comprehensive Income
Comprehensive Income | 12 Months Ended |
Dec. 31, 2018 | |
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] | |
Comprehensive Income | COMPREHENSIVE INCOME We record deferred gains (losses) in AOCI related to interest rate swaps designated as cash flow hedges and the amortization of components of our defined benefit plans. Deferred gains (losses) related to our interest rate swaps are recognized in earnings as they are amortized. The components of the reclassification adjustments for the period, net of tax, included in Other Comprehensive Income were as follows (in thousands): Location on the Statements of Income (Loss) Amounts Reclassified from AOCI 2018 2017 Gains and (losses) on cash flow hedges: Interest rate swaps Interest expense $ 64 $ 64 Income tax Income tax benefit (expense) (13 ) (22 ) Total reclassification adjustments related to cash flow hedges, net of tax $ 51 $ 42 Amortization of defined benefit plans: Actuarial gain (loss) Operations and maintenance $ 103 $ 86 Income tax Income tax benefit (expense) (22 ) (30 ) Total reclassification adjustments related to defined benefit plans, net of tax $ 81 $ 56 Derivatives designated as cash flow hedges relate to a treasury lock entered into in August 2002 to hedge $50 million of our First Mortgage Bonds due on August 15, 2032 . The treasury lock cash settled on August 8, 2002 , the bond pricing date, and resulted in a $1.8 million loss. The treasury lock is treated as a cash flow hedge and the resulting loss is carried in Accumulated other comprehensive loss and is being amortized over the life of the related bonds. Balances by classification included within Accumulated other comprehensive loss on the accompanying Balance Sheets were as follows (in thousands): Interest Rate Swaps Employee Benefit Plans Total As of December 31, 2017 $ (551 ) $ (707 ) $ (1,258 ) Other comprehensive income (loss) before reclassifications — 235 235 Amounts reclassified from AOCI 51 81 132 As of December 31, 2018 $ (500 ) $ (391 ) $ (891 ) Interest Rate Swaps Employee Benefit Plans Total As of December 31, 2016 $ (593 ) $ (669 ) $ (1,262 ) Other comprehensive income (loss) before reclassifications — (94 ) (94 ) Amounts reclassified from AOCI 42 56 98 As of December 31, 2017 $ (551 ) $ (707 ) $ (1,258 ) |
Employee Benefit Plans
Employee Benefit Plans | 12 Months Ended |
Dec. 31, 2018 | |
Defined Benefit Plan [Abstract] | |
Employee Benefit Plans | EMPLOYEE BENEFIT PLANS Defined Contribution Plans BHC sponsors a 401(k) retirement savings plan (the 401(k) Plan). Participants in the 401(k) Plan may elect to invest a portion of their eligible compensation to the 401(k) Plan up to the maximum amounts established by the IRS. The 401(k) Plan provides employees the opportunity to invest up to 50% of their eligible compensation on a pre-tax or after-tax basis. The 401(k) Plan provides a Company matching contribution for all eligible participants. Certain eligible participants who are not currently accruing a benefit in the Pension Plan also receive a Company retirement contribution based on the participant’s age and years of service. Vesting of all Company and matching contributions occurs at 20% per year with 100% vesting when the participant has 5 years of service with the Company. Defined Benefit Pension Plan (Pension Plan) We have a defined benefit pension plan (“Pension Plan”) covering certain eligible employees. The benefits for the Pension Plan are based on years of service and calculations of average earnings during a specific time period prior to retirement. The Pension Plan has been closed to new employees and certain employees who did not meet age and service based criteria. The Pension Plan assets are held in a Master Trust. Our Board of Directors has approved the Pension Plan’s investment policy. The objective of the investment policy is to manage assets in such a way that will allow the eventual settlement of our obligations to the Pension Plan’s beneficiaries. To meet this objective, our pension assets are managed by an outside adviser using a portfolio strategy that will provide liquidity to meet the Pension Plan’s benefit payment obligations. The Pension Plan’s assets consist primarily of equity, fixed income and hedged investments. The expected rate of return on the Pension Plan assets is determined by reviewing the historical and expected returns of both equity and fixed income markets, taking into account asset allocation, the correlation between asset class returns, and the mix of active and passive investments. The Pension Plan utilizes a dynamic asset allocation where the target allocation range to return-seeking and liability-hedging assets is determined based on the funded status of the Plan. As of December 31, 2018 , the expected rate of return on pension plan assets is based on the targeted asset allocation range of 29% to 37% return-seeking assets and 63% to 71% liability-hedging assets. Our Pension Plan is funded in compliance with the federal government’s funding requirements. Plan Assets The percentages of total plan asset by investment category of our Pension Plan assets at December 31 were as follows: 2018 2017 Equity securities 17 % 26 % Real estate 4 4 Fixed income funds 71 63 Cash and cash equivalents 3 1 Hedge funds 5 6 Total 100 % 100 % Supplemental Non-qualified Defined Benefit Plans We have various supplemental retirement plans for key executives of the Company. The plans are non-qualified defined benefit and defined contribution plans (Supplemental Plans). The Supplemental Plans are subject to various vesting schedules and are not funded by the Company. Plan Assets We do not fund our Supplemental Plans. We fund on a cash basis as benefits are paid. Non-pension Defined Benefit Postretirement Healthcare Plans BHC sponsors retiree healthcare plans (Healthcare Plans) for employees who meet certain age and service requirements at retirement. Healthcare Plan benefits are subject to premiums, deductibles, co-payment provisions and other limitations. Pre-65 retirees receive their retiree medical benefits through the Black Hills self-insured retiree medical plans. Healthcare coverage for Medicare-eligible BHP retirees is provided through an individual market healthcare exchange. Plan Assets We fund our Healthcare Plans on a cash basis as benefits are paid. Plan Contributions Contributions to the Pension Plan are cash contributions made directly to the Master Trust. Healthcare benefits include company and participant paid premiums. Contributions for the years ended December 31 were as follows (in thousands): 2018 2017 Defined Contribution Plans Company Retirement Contribution $ 876 $ 861 Matching Contributions $ 1,272 $ 1,306 2018 2017 Defined Benefit Plans Defined Benefit Pension Plan $ 1,795 $ 4,000 Non-Pension Defined Benefit Postretirement Healthcare Plans $ 388 $ 348 Supplemental Non-qualified Defined Benefit Plan $ 238 $ 246 While we do not have required contributions, we expect to make approximately $1.8 million in contributions to our Pension Plan in 2019 . Fair Value Measurements Assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement requires judgment and may affect their placement within the fair value hierarchy levels. The following tables set forth, by level within the fair value hierarchy, the assets that were accounted for at fair value on a recurring basis (in thousands): Pension Plan December 31, 2018 Level 1 Level 2 Level 3 Total Investments Measured at Fair Value NAV (a) Total Investments AXA Equitable General Fixed Income $ — $ 261 $ — $ 261 $ — $ 261 Common Collective Trust - Cash and Cash Equivalents — 1,388 — 1,388 — 1,388 Common Collective Trust - Equity — 9,436 — 9,436 — 9,436 Common Collective Trust - Fixed Income — 39,047 — 39,047 — 39,047 Common Collective Trust - Real Estate — 9 — 9 1,896 1,905 Hedge Funds — — — — 2,627 2,627 Total investments measured at fair value $ — $ 50,141 $ — $ 50,141 $ 4,523 $ 54,664 Pension Plan December 31, 2017 Level 1 Level 2 Level 3 Total Investments Measured at Fair Value NAV (a) Total Investments AXA Equitable General Fixed Income $ — $ 184 $ — $ 184 $ — $ 184 Common Collective Trust - Cash and Cash Equivalents — 314 — 314 — 314 Common Collective Trust - Equity — 15,749 — 15,749 — 15,749 Common Collective Trust - Fixed Income — 37,732 — 37,732 — 37,732 Common Collective Trust - Real Estate — 249 — 249 2,258 2,507 Hedge Funds — — — — 3,398 3,398 Total investments measured at fair value $ — $ 54,228 $ — $ 54,228 $ 5,656 $ 59,884 ________________________ (a) Certain investments that are measured at fair value using Net Asset Value “NAV” per share (or its equivalent) for practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in these tables for these investments are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the reconciliation of changes in the plan’s benefit obligations and fair value of plan assets above. AXA Equitable General Fixed Income Fund : This fund is a diversified portfolio, primarily composed of fixed income instruments. Assets are invested in long-term holdings, such as commercial, agricultural and residential mortgages, publicly traded and privately placed bonds and real estate as well as short-term bonds. Fair values of mortgage loans are measured by discounting future contractual cash flows to be received on the mortgage loans using interest rates of loans with similar characteristics. The discount rate is derived from taking the appropriate U.S. Treasury rate with a like term. The fair value of public fixed maturity securities are generally based on prices obtained from independent valuation service providers with reasonableness prices compared with directly observable market trades. The fair value of privately placed securities are determined using a discounted cash flow model. These models use observable inputs with a discount rate based upon the average of spread surveys collected from private market intermediaries and industry sector of the issuer. The Plan’s investments in the AXA Equitable General Fixed Income Fund are categorized as Level 2. Common Collective Trust Funds: These funds are valued based upon the redemption price of units held by the Plan, which is based on the current fair value of the common collective trust funds’ underlying assets. Unit values are determined by the financial institution sponsoring such funds by dividing the fund’s net assets at fair value by its units outstanding at the valuation dates. The Plan’s investments in common collective trust funds, with the exception of shares of the common collective trust-real estate are categorized as Level 2. Common Collective Trust-Real Estate Fund : This fund is valued based on various factors of the underlying real estate properties, including market rent, market rent growth, occupancy levels, etc. As part of the trustee’s valuation process, properties are externally appraised generally on an annual basis. The appraisals are conducted by reputable independent appraisal firms and signed by appraisers that are members of the Appraisal Institute, with professional designation of Member, Appraisal Institute. All external appraisals are performed in accordance with the Uniform Standards of Professional Appraisal Practices. We receive monthly statements from the trustee, along with the annual schedule of investments and rely on these reports for pricing the units of the fund. The funds without participant withdrawal limitations are categorized as Level 2. The following investments are measured at NAV and are not classified in the fair value hierarchy, in accordance with accounting guidance. Common Collective Trust-Real Estate Fund : This is the same fund as above except that certain of the funds’ assets contain participant withdrawal policies with restrictions on redemption and are therefore not included in the fair value hierarchy. Hedge Funds: These funds represent investments in other investment funds that seek a return utilizing a number of diverse investment strategies. The strategies, when combined aim to reduce volatility and risk while attempting to deliver positive returns under all market conditions. Amounts are reported on a one-month lag. The fair value of hedge funds is determined using net asset value per share based on the fair value of the hedge fund’s underlying investments. 20% of the shares may be redeemed at the end of each month with a 10 -day notice and full redemptions are available at the end of each quarter with 45 -day notice, and is limited to a percentage of the total net assets value of the fund. The net asset values are based on the fair value of each fund’s underlying investments. There are no unfunded commitments related to these hedge funds. Other Plan Information The following tables provide a reconciliation of the employee benefit plan obligations, fair value of assets and amounts recognized in the Balance Sheets, components of the net periodic expense and elements of AOCI: Benefit Obligations Defined Benefit Pension Plan Supplemental Non-qualified Defined Benefit Plans Non-pension Defined Benefit Postretirement Healthcare Plans As of December 31 (in thousands) 2018 2017 2018 2017 2018 2017 Change in benefit obligation: Projected benefit obligation at beginning of year $ 67,562 $ 64,973 $ 3,418 $ 3,404 $ 5,970 $ 5,843 Service cost 516 545 — — 193 206 Interest cost 2,194 2,341 108 116 179 176 Actuarial loss (gain) (2,878 ) 4,008 (296 ) 144 (889 ) 130 Benefits paid (3,562 ) (3,445 ) (238 ) (246 ) (389 ) (348 ) Plan participants transfer to affiliate (1,913 ) (860 ) — — (129 ) (137 ) Plan participants’ contributions — — — — 120 100 Projected benefit obligation at end of year $ 61,919 $ 67,562 $ 2,992 $ 3,418 $ 5,055 $ 5,970 Employee Benefit Plan Assets Defined Benefit Pension Plan Supplemental Non-qualified Defined Benefit Plans Non-pension Defined Benefit Postretirement Healthcare Plans As of December 31 (in thousands) 2018 2017 2018 2017 2018 2017 Beginning fair value of plan assets $ 59,884 $ 53,888 $ — $ — $ — $ — Investment income (loss) (1,884 ) 6,150 — — — — Employer contributions 1,795 4,000 238 246 268 248 Retiree contributions — — — — 120 100 Benefits paid (3,563 ) (3,445 ) (238 ) (246 ) (388 ) (348 ) Plan participants transfer to affiliate (1,568 ) (709 ) — — — — Ending fair value of plan assets $ 54,664 $ 59,884 $ — $ — $ — $ — The funded status of the plans and amounts recognized in the Balance Sheets at December 31 consist of (in thousands): Defined Benefit Pension Plan Supplemental Non-qualified Defined Benefit Plans Non-pension Defined Benefit Postretirement Healthcare Plans 2018 2017 2018 2017 2018 2017 Regulatory asset $ 19,099 $ 18,998 $ — $ — $ — $ — Current liability $ — $ — $ 230 $ 245 $ 466 $ 534 Non-current liability $ 7,255 $ 7,676 $ 2,762 $ 3,173 $ 4,589 $ 5,436 Regulatory liability $ — $ — $ — $ — $ 2,441 $ 1,758 Accumulated Benefit Obligation Defined Benefit Pension Plan Supplemental Non-pension Defined Benefit Postretirement Healthcare Plans As of December 31 (in thousands) 2018 2017 2018 2017 2018 2017 Accumulated benefit obligation $ 59,987 $ 64,782 $ 2,992 $ 3,418 $ 5,055 $ 5,970 Components of Net Periodic Expense Net periodic expense consisted of the following for the year ended December 31 (in thousands): Defined Benefit Pension Plan Supplemental Non-pension Defined Benefit Postretirement Healthcare Plan 2018 2017 2016 2018 2017 2016 2018 2017 2016 Service cost $ 516 $ 545 $ 606 $ — $ — $ — $ 193 $ 206 $ 204 Interest cost 2,194 2,341 2,499 108 116 122 179 176 187 Expected return on assets (3,545 ) (3,591 ) (3,632 ) — — — — — — Amortization of prior service cost (credits) 43 43 43 — — — (336 ) (336 ) (337 ) Recognized net actuarial loss (gain) 2,063 1,230 1,995 103 87 82 — — — Net periodic expense $ 1,271 $ 568 $ 1,511 $ 211 $ 203 $ 204 $ 36 $ 46 $ 54 For the year ended December 31, 2018, service costs were recorded in Operations and maintenance expense while non-service costs were recorded in Other expense, on the Statements of Income. For the years ended December 31, 2017 and 2016, service costs and non-service costs were recorded in Operations and maintenance expense. Because prior years’ costs were not considered material, they were not reclassified on the Statements of Income. See Note 1 for additional information. AOCI For defined benefit plans, amounts included in AOCI, after-tax, that have not yet been recognized as components of net periodic benefit cost at December 31 were as follows (in thousands): Defined Benefit Pension Plan Supplemental Non-qualified Defined Benefit Plans Non-pension Defined Benefit Postretirement Healthcare Plan 2018 2017 2018 2017 2018 2017 Net (gain) loss $ — $ — $ 391 $ 707 $ — $ — Total AOCI $ — $ — $ 391 $ 707 $ — $ — Assumptions Defined Benefit Pension Plan Supplemental Non-qualified Defined Benefit Plans Non-pension Defined Benefit Postretirement Healthcare Plan 2018 2017 2016 2018 2017 2016 2018 2017 2016 Weighted-average assumptions used to determine benefit obligations: Discount rate 4.40 % 3.71 % 4.27 % 4.30 % 3.62 % 4.12 % 4.28 % 3.60 % 3.84 % Rate of increase in compensation levels 3.52 % 3.43 % 3.47 % N/A N/A N/A N/A N/A N/A Weighted-average assumptions used to determine net periodic benefit cost for plan year: Discount rate (a) 3.71 % 4.27 % 4.63 % 3.62 % 4.12 % 4.29 % 3.60 % 3.84 % 4.03 % Expected long-term rate of return on assets (b) 6.25 % 6.75 % 6.75 % N/A N/A N/A 3.93 % N/A N/A Rate of increase in compensation levels 3.43 % 3.47 % 3.57 % N/A N/A N/A N/A N/A N/A _____________________________ (a) The estimated discount rate for the Defined Benefit Pension Plan is 4.40% for the calculation of the 2019 net periodic pension costs. (b) The expected rate of return on plan assets is 6.00% for the calculation of the 2019 net periodic pension cost. The healthcare benefit obligation was determined at December 31 as follows: 2018 2017 Trend Rate - Medical Pre-65 for next year 6.70 % 7.00 % Pre-65 Ultimate trend rate 4.50 % 4.50 % Trend Year 2027 2027 Post-65 for next year 4.94 % 5.00 % Post-65 Ultimate trend rate 4.50 % 4.50 % Trend Year 2026 2026 Beginning in 2016, we changed the method used to estimate the service and interest cost components of the net periodic pension, supplemental non-qualified defined benefit and other postretirement benefit costs. See “Pension and Postretirement Benefit Obligations” within our Critical Accounting Policies in Item 7 on this Form 10-K for additional details. The following benefit payments, which reflect future service, are expected to be paid (in thousands): Defined Benefit Pension Plan Supplemental Non-qualified Defined Benefit Plans Non-Pension Defined Benefit Postretirement Healthcare Plan 2019 $ 3,660 $ 230 $ 466 2020 $ 3,774 $ 227 $ 534 2021 $ 3,924 $ 322 $ 566 2022 $ 4,031 $ 319 $ 577 2023 $ 4,102 $ 315 $ 554 2024-2028 $ 20,759 $ 1,274 $ 2,243 |
Related-Party Transactions
Related-Party Transactions | 12 Months Ended |
Dec. 31, 2018 | |
Related Party Transactions [Abstract] | |
Related-Party Transactions | RELATED-PARTY TRANSACTIONS Non-Cash Dividend to Parent We recorded non-cash dividends to our Parent of $36 million and $42 million in 2018 and 2017 respectively, and changed the Utility Money Pool note by $36 million and $42 million in 2018 and 2017 , respectively. Receivables and Payables We have accounts receivable and accounts payable balances related to transactions with other BHC subsidiaries. These balances as of December 31 were as follows (in thousands): 2018 2017 Accounts receivable from affiliates $ 8,119 $ 5,664 Accounts payable to affiliates $ 25,804 $ 25,653 Money Pool Notes Receivable and Notes Payable We participate in the Utility Money Pool Agreement (the Agreement). Under the Agreement, we may borrow from the pool; however the Agreement restricts the pool from loaning funds to BHC or to any of BHC’s non-utility subsidiaries. The Agreement does not restrict us from paying dividends to BHC. Borrowings under the Agreement bear interest at the weighted average daily cost of BHC’s external borrowings as defined under the Agreement, or if there are no external funds outstanding on that date, then the rate will be the daily one-month LIBOR plus 1.0% . The cost of borrowing under the Utility Money Pool was 3.06% at December 31, 2018 . We had the following balances with the Utility Money Pool as of December 31 (in thousands): 2018 2017 Money pool notes payable $ 38,690 $ 13,397 Interest income relating to the Utility Money Pool for the years ended December 31, was as follows (in thousands): 2018 2017 2016 Interest income (expense) $ (401 ) $ 272 $ 1,047 Interest expense allocation from Parent BHC provides daily liquidity and cash management on behalf of all its subsidiaries. For the years ended December 31, 2018 , 2017 and 2016 , we were allocated $1.3 million , $1.4 million , and $1.9 million , respectively, of interest expense from BHC. Other Balances and Transactions We have the following Power Purchase, Transmission Services , and Ground Lease Agreements with affiliated entities: • An agreement, expiring September 3, 2028 , with Wyoming Electric to acquire 15 MW of the facility output from Happy Jack. Under a separate inter-company agreement expiring on September 3, 2028 , Wyoming Electric has agreed to sell up to 15 MW of the facility output from Happy Jack to us. • An agreement, expiring September 30, 2029 , with Wyoming Electric to acquire 20 MW of the facility output from Silver Sage. Under a separate inter-company agreement expiring on September 30, 2029 , Wyoming Electric has agreed to sell 20 MW of energy from Silver Sage to us. • A Generation Dispatch Agreement with Wyoming Electric that requires us to purchase all of Wyoming Electric’s excess energy. • A Wygen III Ground Lease with WDRC expiring in 2050 with three automatic renewal terms of 20 years each. Related-party Gas Transportation Service Agreement On October 1, 2014, we entered into a gas transportation service agreement with Wyoming Electric in connection with gas supply for Cheyenne Prairie. The agreement is for a term of 40 years , in which we pay a monthly service and facility fee for firm and interruptible gas transportation. Related-party Revenue and Purchases We had the following related-party transactions for the years ended December 31 included in the corresponding captions in the accompanying Statements of Income: 2018 2017 2016 (in thousands) Revenues: Energy sold to Cheyenne Light $ 2,064 $ 2,481 $ 2,440 Rent from electric properties $ 3,634 $ 3,680 $ 5,046 Horizon Point shared facility revenue $ 11,211 $ 1,420 $ — Fuel and purchased power: Purchases of coal from WRDC $ 17,532 $ 15,948 $ 16,227 Purchase of excess energy from Cheyenne Light $ 511 $ 601 $ 252 Purchase of renewable wind energy from Cheyenne Light - Happy Jack $ 1,942 $ 1,924 $ 1,918 Purchase of renewable wind energy from Cheyenne Light - Silver Sage $ 3,586 $ 3,290 $ 3,300 Gas transportation service agreement with Cheyenne Light for firm and interruptible gas transportation $ 364 $ 393 $ 399 Related-party Corporate Support We had the following corporate support for the years ended December 31: 2018 2017 2016 (in thousands) Corporate support services and fees from Parent, Black Hills Service Company and Black Hills Utility Holdings $ 34,578 $ 27,869 $ 25,748 Horizon Point Agreement We have a shared facility agreement among South Dakota Electric, Black Hills Service Company, and Black Hills Utility Holdings where there is a cost allocation for the use of the Horizon Point facility that is owned by South Dakota Electric. This cost allocation includes the recovery of and return on allocable property and recovery of incurred administrative service expenses for the operation and maintenance of the Horizon Point facility. |
Supplemental Cash Flow Informat
Supplemental Cash Flow Information | 12 Months Ended |
Dec. 31, 2018 | |
Supplemental Cash Flow Information [Abstract] | |
Supplemental Cash Flow Information | SUPPLEMENTAL CASH FLOW INFORMATION Years ended December 31, 2018 2017 2016 (in thousands) Non-cash investing and financing activities - Property, plant and equipment acquired with accrued liabilities $ 15,180 $ 6,565 $ 5,521 Non-cash decrease to money pool note receivable, net $ (36,000 ) $ (42,000 ) $ (52,500 ) Non-cash dividend to Parent $ 36,000 $ 42,000 $ 52,500 Cash (paid) refunded during the period for - Interest (net of amounts capitalized) $ (21,988 ) $ (21,517 ) $ (21,320 ) Income taxes (paid) refunded $ (10,394 ) $ (12,719 ) $ — |
Commitment and Contingencies
Commitment and Contingencies | 12 Months Ended |
Dec. 31, 2018 | |
Commitments and Contingencies Disclosure [Abstract] | |
Commitments and Contingencies | COMMITMENTS AND CONTINGENCIES Power Purchase and Transmission Services Agreements We have the following power purchase and transmission services agreements, not including related party agreements, as of December 31, 2018 (see Note 9 for information on related party agreements): • A PPA with PacifiCorp, expiring December 31, 2023 , for the purchase of 50 MW of electric capacity and energy from PacifiCorp’s system. The price paid for the capacity and energy is based on the operating costs of one of PacifiCorp’s coal-fired electric generating plants. • A firm point-to-point transmission service agreement with PacifiCorp that expires December 31, 2023 . The agreement provides 50 MW of capacity and energy to be transmitted annually by PacifiCorp. • An agreement with Thunder Creek for gas transport capacity, expiring October 31, 2019 . • A PPA with Platte River Power Authority (PRPA) to purchase up to 12 MW of wind energy through PRPA’s agreement with Silver Sage. This agreement will expire September 30, 2029 . Costs incurred under these agreements were as follows for the years ended December 31 (in thousands): Contract Contract Type 2018 2017 2016 PacifiCorp Electric capacity and energy $ 13,681 $ 13,218 $ 12,221 PacifiCorp Transmission access $ 1,742 $ 1,671 $ 1,428 Thunder Creek Gas transport capacity $ 633 $ 633 $ 633 Platte River Power Authority Wind energy $ 223 $ — $ — Future Contractual Obligations The following is a schedule of future minimum payments required under power purchase, transmission services, land and facility operating leases, and gas supply agreements (in thousands): 2019 $ 8,050 2020 $ 7,693 2021 $ 7,059 2022 $ 7,059 2023 $ 7,056 Thereafter $ 21,947 Long-Term Power Sales Agreements We have the following power sales agreements as of December 31, 2018 : • During periods of reduced production at Wygen III in which MDU owns a portion of the capacity, or during periods when Wygen III is off-line, MDU will be provided with 25 MW from our other generation facilities or from system purchases with reimbursement of costs by MDU. This agreement expires January 31, 2023 . • An agreement to serve MDU capacity and energy up to a maximum of 50 MW in excess of Wygen III ownership. This agreement expires December 31, 2023 . • During periods of reduced production at Wygen III in which the City of Gillette owns a portion of the capacity, or during periods when Wygen III is off-line, we will provide the City of Gillette with its first 23 MW from our other generating facilities or from system purchases with reimbursement of costs by the City of Gillette. Under this agreement, which expires September 3, 2019 , South Dakota Electric will also provide the City of Gillette their operating component of spinning reserves. • A PPA with MEAN expiring May 31, 2028 . This contract is unit-contingent on up to 10 MW from Neil Simpson II and up to 10 MW from Wygen III based on the availability of these plants. The capacity purchase requirements decrease over the term of the agreement. • An agreement through December 31, 2021 to provide 50 MW of energy to Macquarie Energy, LLC during heavy and light load timing intervals. Environmental Matters We are subject to costs resulting from a number of federal, state and local laws and regulations which affect future planning and existing operations. They can result in increased capital expenditures, operating and other costs as a result of compliance, remediation and monitoring obligations. Due to the environmental issues discussed below, we may be required to modify, curtail, replace or cease operating certain facilities or operations to comply with statutes, regulations and other requirements of regulatory bodies. Solid Waste Disposal Various materials used at our facilities are subject to disposal regulations. Our Osage plant, permanently retired on March 21, 2014, had an on-site ash impoundment that was near capacity. An application to close the impoundment was approved on April 13, 2012. Site closure work was completed in 2013 with the state providing closure certification in 2014. Post closure monitoring activities will continue for 30 years following the closure certification date. In September 2013, Osage also received a permit to close the small industrial rubble landfill. Site work was completed with the state providing closure certification in 2014. Post closure monitoring will continue for 30 years following the closure certification date. For additional information on environmental matters, see Item 1 in this Annual Report on Form 10-K. Legal Proceedings In the normal course of business, we are subject to various lawsuits, actions, proceedings, claims and other matters asserted under laws and regulations. We believe the amounts provided in the financial statements to satisfy alleged liabilities are adequate in light of the probable and estimable contingencies. However, there can be no assurance that the actual amounts required to satisfy alleged liabilities from various legal proceedings, claims and other matters discussed, and to comply with applicable laws and regulations will not exceed the amounts reflected in the financial statements. In the normal course of business, we enter into agreements that include indemnification in favor of third parties, such as information technology agreements, purchase and sale agreements and lease contracts. We have also agreed to indemnify our directors, officers and employees in accordance with our articles of incorporation, as amended. Certain agreements do not contain any limits on our liability and therefore, it is not possible to estimate our potential liability under these indemnifications. In certain cases, we have recourse against third parties with respect to these indemnities. Further, we maintain insurance policies that may provide coverage against certain claims under these indemnities. |
Quarterly Historical Data (Unau
Quarterly Historical Data (Unaudited) | 12 Months Ended |
Dec. 31, 2018 | |
Selected Quarterly Financial Information [Abstract] | |
Quarterly Historical Data (Unaudited) | QUARTERLY HISTORICAL DATA (Unaudited) We operate on a calendar year basis. The following table sets forth selected unaudited historical operating results data for each quarter (in thousands): First Quarter Second Quarter Third Quarter Fourth Quarter 2018 Revenues $ 73,815 $ 70,676 $ 78,067 $ 75,522 Operating income $ 20,364 $ 19,495 $ 21,428 $ 17,048 Net income $ 11,760 $ 11,125 $ 13,317 $ 9,443 2017 Revenues $ 73,794 $ 66,053 $ 73,938 $ 74,648 Operating income $ 23,376 $ 17,712 $ 23,698 $ 19,040 Net income $ 12,570 $ 9,287 $ 13,826 $ 15,615 In 2018, we recorded $0.9 million of income tax expense associated with changes in the prior estimated impact of tax reform on deferred income taxes compared to a net tax benefit of $6.0 million in 2017 as a result of the revaluation of deferred tax balances due to the decrease in the statutory Federal income tax rate as a result of the TCJA. |
Business Description and Summ_2
Business Description and Summary of Significant Accounting Policies (Policies) | 12 Months Ended |
Dec. 31, 2018 | |
Organization, Consolidation and Presentation of Financial Statements [Abstract] | |
Basis of Presentation | Basis of Presentation The financial statements include the accounts of Black Hills Power, Inc. and also our ownership interests in the assets, liabilities and expenses of our jointly owned facilities (Note 3 ) and are prepared in accordance with GAAP. |
Use of Estimates and Basis of Presentation | Use of Estimates and Basis of Presentation The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Changes in facts and circumstances or additional information may result in revised estimates and actual results could differ materially from those estimates. |
Cash Equivalents | Cash Equivalents We consider all highly liquid investments with an original maturity of three months or less to be cash equivalents. As of December 31, 2018 and 2017, we have no cash equivalents. |
Regulatory Accounting | Regulatory Accounting Our regulated electric operations are subject to regulation by various state and federal agencies. The accounting policies followed are generally subject to the Uniform System of Accounts of FERC. If rate recovery becomes unlikely or uncertain due to competition or regulatory action, these accounting standards may no longer apply which could require these net regulatory assets to be charged to current income or OCI. Our regulatory assets represent amounts for which we will recover the cost, but generally are not allowed a return, except as described below. In the event we determine that our regulated net assets no longer meet the criteria for accounting standards for regulated operations, the accounting impact to us could be an extraordinary non-cash charge to operations, which could be material. We had the following regulatory assets and liabilities as of December 31 (in thousands): 2018 2017 Regulatory assets Loss on reacquired debt (a) $ 1,259 $ 1,534 Deferred taxes on AFUDC (b) 5,020 5,095 Employee benefit plans and related deferred taxes (c) 19,868 19,465 Deferred energy and fuel cost adjustments (a) 20,334 19,602 Deferred taxes on flow through accounting (c) 8,749 7,579 Decommissioning costs (b) 8,196 10,252 Vegetation management (a) 10,366 12,669 Other regulatory assets (a) 1,940 2,507 $ 75,732 $ 78,703 Less current regulatory assets (19,052 ) (18,993 ) Regulatory assets, non-current $ 56,680 $ 59,710 Regulatory liabilities Cost of removal for utility plant (a) $ 52,366 $ 44,056 Employee benefit plans and related deferred taxes (c) 7,518 6,808 Excess deferred income taxes (c) 100,276 97,101 TCJA revenue reserve 2,523 — Other regulatory liabilities (c) 533 890 $ 163,216 $ 148,855 Less current regulatory liabilities (2,574 ) (842 ) Regulatory liabilities, non-current $ 160,642 $ 148,013 ____________________ (a) We are allowed a recovery of costs but we are not allowed a rate of return. (b) In addition to recovery of costs, we are allowed a rate of return. (c) In addition to recovery or repayment of costs, we are allowed a return on a portion of this amount or a reduction in rate base. Regulatory assets represent items we expect to recover from customers through probable future increases in rates. Loss on Reacquired Debt - The early redemption premium on reacquired debt is being amortized over the remaining term of the original bonds. Deferred Taxes on AFUDC - The equity component of AFUDC is considered a permanent difference for tax purposes with the tax benefit being flowed through to customers as prescribed or allowed by regulators. If, based on a regulator’s action, it is probable the utility will recover the future increase in taxes payable represented by this flow-through treatment through a rate revenue increase, a regulatory asset is recognized. This regulatory asset itself is a temporary difference for which a deferred tax liability must be recognized. Accounting standards for income taxes specifically address AFUDC-equity, and require a gross-up of such amounts to reflect the revenue requirement associated with a rate-regulated environment. Employee Benefit Plans - Employee benefit plans include the unrecognized prior service costs and net actuarial loss associated with our defined benefit pension plan and other post-retirement benefit plans in regulatory assets rather than in accumulated other comprehensive income. In addition, this regulatory asset includes the income tax effect of the adjustment required under accounting for compensation-defined benefit plans to record the full pension and post-retirement benefit obligations. Such amounts have been grossed-up to reflect the revenue requirement associated with a rate regulated environment. Deferred Energy and Fuel Cost Adjustments - Deferred energy and fuel cost adjustments represent the cost of electricity delivered to our customers that is either higher or lower than the current rates and will be recovered or refunded in future rates. Deferred energy and fuel cost adjustments are recorded and recovered or amortized as approved by the appropriate state commission. We file periodic quarterly, semi-annual and/or annual filings to recover these costs based on the respective cost mechanisms approved by the applicable state utility commissions. Deferred Taxes on Flow-Through Accounting - Under flow-through accounting, the income tax effects of certain tax items are reflected in our cost of service for the customer in the year in which the tax benefits are realized and result in lower utility rates. A regulatory asset was established to reflect that future increases in income taxes payable will be recovered from customers as the temporary differences reverse. As a result of this regulatory treatment, we continue to record a tax benefit for costs considered currently deductible for tax purposes, but are capitalized for book purposes. Decommissioning Costs - We received approval in 2014 for regulatory treatment on the remaining net book values and decommissioning costs of our decommissioned coal plants. Vegetation Management Costs - We received approval in 2013 for regulatory treatment on vegetation management maintenance costs for our distribution system rights-of-way. Regulatory liabilities represent items we expect to refund to customers through probable future decreases in rates. Cost of Removal for Utility Plant - Cost of removal for utility plant represents the estimated cumulative net provisions for future removal costs included in depreciation expense for which there is no legal obligation for removal. Employee Benefit Plans - Employee benefit plans represent the cumulative excess of pension and other postretirement benefit costs recovered in rates over pension expense recorded in accordance with accounting standards for compensation-retirement benefits. In addition, this regulatory liability includes the income tax effect of the adjustment required under accounting for compensation-defined benefit plans, to record the full pension and post-retirement benefit obligations. Such income tax effect has been grossed-up to account for the revenue requirement associated with a rate regulated environment. Excess Deferred Income Taxes - The revaluation of our deferred tax assets and liabilities due to the passage of the TCJA is recorded as an excess deferred income tax to be refunded to customers primarily using the normalization principles as prescribed in the TCJA. See additional details below. TCJA Revenue Reserve - Revenue subject to refund at December 31, 2018, represents revenue reserved as a result of the TCJA. See below “ TCJA Revenue Reserve ” under Revenue recognition for further disclosure. Excess Deferred Income Taxes As of December 31, 2018 and 2017 , we have a regulatory liability associated with TCJA related items of approximately $100 million and $97 million , respectively. The majority of this regulatory liability relates to excess deferred taxes resulting from the remeasurement of deferred tax assets and liabilities in 2017. A significant portion of the excess deferred taxes are subject to the average rate assumption method, as prescribed by the IRS, and will generally be amortized as a reduction of customer rates over the remaining lives of the related assets. As of December 31, 2018, the Company has amortized $0.9 million of this regulatory liability. The portion that was eligible for amortization under the average rate assumption method in 2018, but is awaiting resolution of the treatment of these amounts in future regulatory proceedings, has not been recognized and may be refunded in customer rates at any time in accordance with the resolution of pending or future regulatory proceedings. See Note 6 for more information. |
Accounts Receivable and Allowance for Doubtful Accounts | Accounts Receivable and Allowance for Doubtful Accounts Accounts receivable consists of sales to residential, commercial, industrial, municipal and other customers all of which do not bear interest. These accounts receivable are stated at billed and unbilled amounts, net of write-offs or payment received. We maintain an allowance for doubtful accounts which reflects our best estimate of uncollectible trade receivables. We regularly review our trade receivable allowances by considering such factors as historical experience, credit worthiness, the age of the receivable balances and current economic conditions that may affect collectibility. In specific cases where we are aware of a customer’s inability or reluctance to pay, we record an allowance for doubtful accounts to reduce the net receivable balance to the amount we reasonably expect to collect. However, if circumstances change, our estimate of the recoverability of accounts receivable could be affected. Circumstances which could affect our estimates include, but are not limited to, customer credit issues, the level of commodity prices, customer deposits and general economic conditions. Accounts are written off once they are deemed to be uncollectible or the time allowed for dispute under the contract has expired. |
Revenue Recognition | Revenue Recognition Revenues are recognized in an amount that reflects the consideration we expect to receive in exchange for goods or services, when control of the promised goods or services is transferred to our customers. Our primary types of revenue contracts are: • Regulated electric utility services tariffs - Our regulated operations, as defined by ASC 980, provide services to regulated customers under rates, charges, terms and conditions of service, and prices determined by the jurisdictional regulators designated for our service territories. Collectively, these rates, charges, terms and conditions are included in a tariff, which governs all aspects of the provision of our regulated services. Our regulated services primarily encompass single performance obligations material to the context of the contract for delivery of commodity electricity and electric transmission services. These service revenues are variable based on quantities delivered, influenced by seasonal business and weather patterns. Tariffs are only permitted to be changed through a rate-setting process involving the regulator-empowered statute to establish contractual rates between the utility and its customers. All of our regulated utility sales are subject to regulatory-approved tariffs. • Power sales agreements - We have long-term wholesale power sales agreements with other load serving entities, including affiliates, for the sale of excess power from owned generating units. These agreements include a combination of “take or pay” arrangements, where the customer is obligated to pay for the energy regardless of whether it actually takes delivery, as well as “requirements only” arrangements, where the customer is only obligated to pay for the energy the customer needs. In addition to these long-term contracts, the Company also sells excess energy to other load-serving entities on a short-term basis. The pricing for all of these arrangements is included in the executed contracts or confirmations, reflecting the standalone selling price, and is variable based on energy delivered. The following table depicts the disaggregation of revenue, including intercompany revenue, from contracts with customers by customer type and timing of revenue recognition. Sales tax and other similar taxes are excluded from revenues. Year ended December 31, 2018 (in thousands) Customer types: Retail $ 197,184 Wholesale 33,687 Market - off-system sales 17,691 Transmission/Other 49,015 Revenue from contracts with customers 297,577 Other revenues 503 Total revenues $ 298,080 Timing of revenue recognition: Services transferred over time $ 297,577 Revenue from contracts with customers $ 297,577 The majority of the our revenue contracts are based on variable quantities delivered; any fixed consideration contracts with an expected duration of one year or more are immaterial to our revenues. Variable consideration constraints in the form of discounts, rebates, credits, price concessions, incentives, performance bonuses, penalties or other similar items are not material for our revenue contracts. We are the principal in our revenue contracts, as we have control over the services prior to those services being transferred to the customer. Revenue Not in Scope of ASC 606 Other revenues included in the table above include revenue accounted for under separate accounting guidance, including alternative revenue programs revenue under ASC 980. Significant Judgments and Estimates TCJA revenue reserve The TCJA or “tax reform”, signed into law on December 22, 2017, reduced the federal corporate income tax rate from 35% to 21% effective for tax years beginning after December 31, 2017. We have been collaborating with our regulators in the states in which we provide utility service to deliver to customers the benefits of a lower corporate federal income tax rate beginning in 2018 with the passage of the TCJA. We estimated and recorded a revenue reserve of approximately $10 million during the year ended December 31, 2018. On September 4, 2018, the SDPUC approved a settlement agreement for South Dakota Electric allowing the Company to pass on the benefits of a lower corporate federal income tax rate to our South Dakota retail customers. As of December 31, 2018, approximately $7.6 million has been delivered to customers and approximately $2.5 million remains in reserve. Unbilled Revenue To the extent that deliveries have occurred but a bill has not been issued, the Company accrues an estimate of the revenue since the latest billing. This estimate is calculated based on several factors including billings through the last billing cycle in a month and prices in effect in our jurisdictions. Each month the estimated unbilled revenue amounts are trued-up and recorded in Accounts receivable, net on the accompanying Balance Sheets. Contract Balances The nature of our primary revenue contracts provides an unconditional right to consideration upon service delivery; therefore, no customer contract assets or liabilities exist. The unconditional right to consideration is represented by the balance in our Accounts Receivable and is further discussed above. We do not typically incur costs that would be capitalized, to obtain or fulfill a contract. Practical Expedients Our revenue contracts generally provide for performance obligations that are fulfilled and transfer control to customers over time, represent a series of distinct services that are substantially the same, involve the same pattern of transfer to the customer, and provide a right to consideration from our customers in an amount that corresponds directly with the value to the customer for the performance completed to date. Therefore, we recognize revenue in the amount to which we have a right to invoice. We have revenue contract performance obligations with similar characteristics, and we reasonably expect that the financial statement impact of applying the new revenue recognition guidance to a portfolio of contracts would not differ materially from applying this guidance to the individual contracts or performance obligations within the portfolio. Therefore, we have elected the portfolio approach in applying the new revenue guidance. |
Materials, Supplies, and Fuel | Materials, Supplies and Fuel Materials, supplies and fuel used for construction, operation and maintenance purposes are recorded using the weighted-average cost method. |
Deferred Financing Costs | Deferred Financing Costs Deferred financing costs are amortized over the estimated useful life of the related debt. Deferred financing costs are presented on the balance sheet as an adjustment to the related debt liabilities. |
Property, Plant and Equipment | Property, Plant and Equipment Additions to property, plant and equipment are recorded at cost. Included in the cost of regulated construction projects is AFUDC, when applicable, which represents the approximate composite cost of borrowed funds and a return on equity used to finance a regulated utility project. We also capitalize interest, when applicable, on undeveloped leasehold costs and certain non-regulated construction projects. In addition, asset retirement costs associated with tangible long-lived regulated utility assets are recognized as liabilities with an increase to the carrying amounts of the related long-lived regulated utility assets in the period incurred. The amounts capitalized are included in Property, plant and equipment on the accompanying Balance Sheets. The cost of regulated utility property, plant and equipment retired, or otherwise disposed of in the ordinary course of business, less salvage plus retirement costs, is charged to accumulated depreciation. Estimated removal costs associated with non-legal retirement obligations related to our regulated electric properties are reclassified from accumulated depreciation and reflected as regulatory liabilities. Ordinary repairs and maintenance of property, except as allowed under rate regulations, are charged to operations as incurred. Property, plant and equipment is tested for impairment when it is determined that the carrying value of the assets may not be recoverable. A loss is recognized in the current period if it becomes probable that part of a cost of a plant under construction or recently completed plant will be disallowed for recovery from customers and a reasonable estimate of the disallowance can be made. For investments in property, plant and equipment that are abandoned and not expected to go into service, incurred costs and related deferred tax amounts are compared to the discounted estimated future rate recovery, and a loss is recognized, if necessary. Depreciation provisions for regulated electric property, plant and equipment are computed on a straight-line basis using an annual composite rate of 2.3% in 2018 , 2.1% in 2017 and 2.2% in 2016 . |
Derivatives and Hedging Activities | Derivatives and Hedging Activities The accounting standards for derivatives and hedging require that derivative instruments be recorded on the balance sheet as either an asset or liability measured at its fair value and changes in the derivative instruments be recognized in earnings unless specific hedge accounting criteria are met and designated accordingly, including the normal purchase and normal sales exception. Changes in the fair value for derivative instruments that do not meet this exception are recognized in the income statement as they occur. From time to time we utilize risk management contracts including interest rate swaps to fix the interest on variable rate debt, or to lock in the Treasury yield component associated with anticipated issuance of senior notes. For swaps that settled in connection with the issuance of senior debt, the effective portion is deferred as a component in AOCI and recognized as interest expense over the life of the senior note. As of December 31, 2018, we have no outstanding interest rate swap agreements. Revenues and expenses on contracts that qualify as derivatives may be elected to be accounted for under the normal purchases and normal sales exception and are recognized when the underlying physical transaction is completed under the accrual basis of accounting. Normal purchases and normal sales are contracts where physical delivery is probable, quantities are expected to be used or sold in the normal course of business over a reasonable amount of time, and price is not tied to an unrelated underlying derivative. As part of our regulated electric operations, we enter into contracts to buy and sell energy to meet the requirements of our customers. These contracts include short-term and long-term commitments to purchase and sell energy in the retail and wholesale markets with the intent and ability to deliver or take delivery. If it was determined that a transaction designated as a normal purchase or normal sale no longer met the exception, the fair value of the related contract would be reflected as either an asset or liability, under the accounting standards for derivatives and hedging. |
Fair Value Measurements | Fair Value Measurements We use the following fair value hierarchy for determining inputs for our financial instruments. Our financial instruments’ assets and liabilities for financial instruments are classified and disclosed in one of the following fair value categories: Level 1 — Unadjusted quoted prices available in active markets that are accessible at the measurement date for identical unrestricted assets or liabilities. Level 1 instruments primarily consist of highly liquid and actively traded financial instruments with quoted pricing information on an ongoing basis. Level 2 — Pricing inputs include quoted prices for identical or similar assets and liabilities in active markets other than quoted prices in Level 1, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability and inputs that are derived principally from or corroborated by observable market data by correlation or other means. Level 3 — Pricing inputs are generally less observable from objective sources. These inputs reflect management’s best estimate of fair value using its own assumptions a market participant would use in pricing the asset or liability. Assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. Our assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the placement within the fair value hierarchy levels. We record transfers, if necessary, between levels at the end of the reporting period for all of our financial instruments. Transfers into Level 3, if any, occur when significant inputs used to value the derivative instruments become less observable such as a significant decrease in the frequency and volume in which the instrument is traded, negatively impacting the availability of observable pricing inputs. Transfers out of Level 3, if any, occur when the significant inputs become more observable such as the time between the valuation date and the delivery date of a transaction becomes shorter, positively impacting the availability of observable pricing inputs. We currently do not have any Level 3 investments. |
Income Taxes | Income Taxes We file a federal income tax return with other members of the Parent’s consolidated group. For financial statement purposes, federal income taxes are allocated to the individual companies based on amounts calculated on a separate return basis. The Company uses the asset and liability method in accounting for income taxes. Under the asset and liability method, deferred income taxes are recognized at currently enacted income tax rates, to reflect the tax effect of temporary differences between the financial and tax basis of assets and liabilities as well as operating loss and tax credit carryforwards. Such temporary differences are the result of provisions in the income tax law that either require or permit certain items to be reported on the income tax return in a different period than they are reported in the financial statements. On December 22, 2017, the U.S. government enacted comprehensive tax legislation commonly referred to as the TCJA. The TCJA makes broad and complex changes to the U.S. tax code, including, but not limited to reducing the U.S. federal corporate tax rate from 35% to 21% . We use the deferral method of accounting for investment tax credits as allowed by our rate-regulated jurisdictions. Such a method results in the investment tax credit being amortized as a reduction to income tax expense over the estimated useful lives of the underlying property that gave rise to the credit. We recognize interest income or interest expense and penalties related to income tax matters in Income tax (expense) benefit on the Statements of Income. We account for uncertainty in income taxes recognized in the financial statements in accordance with the accounting standards for income taxes. The unrecognized tax benefit is classified in Other, non-current liabilities on the accompanying Balance Sheets. |
Recently Issued and Adopted Accounting Standards | Recently Issued Accounting Standards Leases, ASU 2016-02 In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , which supersedes ASC 840, Leases. This ASU requires lessees to recognize a right-of-use asset and lease liability on the balance sheet for most leases, whereas today only financing-type lease liabilities (capital leases) are recognized on the balance sheet. In addition, the definition of a lease has been revised in regards to when an arrangement conveys the right to control the use of the identified asset under the arrangement which may result in changes to the classification of an arrangement as a lease. The ASU does not significantly change the lessees’ recognition, measurement and presentation of expenses and cash flows from the previous accounting standard. Lessors’ accounting under the ASU is largely unchanged from the previous accounting standard. The ASU expands the disclosure requirements of lease arrangements. Under the original guidance, lessees and lessors will use a modified retrospective transition approach, which requires application of the new guidance at the beginning of the earliest comparative period presented in the year of adoption. The guidance is effective for interim and annual reporting periods beginning after December 15, 2018, with early adoption permitted. In January 2018, the FASB issued amendments to the new lease standard, ASU No. 2018-01, allowing an entity to elect not to assess whether certain land easements are, or contain, leases when transitioning to the new lease standard. The FASB also issued additional amendments to the new lease standard in July 2018, ASU No. 2018-11, allowing companies to adopt the new standard with a cumulative effect adjustment as of the beginning of the year of adoption with prior year comparative financial information and disclosures remaining as previously reported. We adopted this standard on January 1, 2019. For existing or expired land easements that were not previously accounted for as a lease, we elected the practical expedient which provides for no assessment of these easements. Further, we adopted the new standard with a cumulative effect adjustment with prior year comparative financial information remaining as previously reported when transitioning to the new standard. The standard also provides a transition practical expedient, commonly referred to as the “package of three”, that must be taken together and allows entities to (1) not reassess whether existing contracts contain leases, (2) carryforward the existing lease classification, and (3) not reassess initial direct costs associated with existing leases. We elected the “package of three” practical expedient. We have implemented a new lease accounting system and adjusted related procedures and controls accordingly. We will record an operating lease right of use asset and an off-setting operating lease obligation liability as of January 1, 2019 for approximately $14 million , respectively, primarily driven by the intercompany ground lease with WRDC for Wygen III. Adoption of this standard did not have a material impact on our financial position, results of operations or cash flows. Recently Adopted Accounting Standards Revenue from Contracts with Customers, ASU 2014-09 Effective January 1, 2018, we adopted ASU 2014-09, Revenue from Contracts with Customers (Topic 606) , and its related amendments (collectively known as ASC 606). Under this standard, revenue is recognized when a customer obtains control of promised goods or services in an amount that reflects the consideration the entity expects to receive in exchange for those goods or services. In addition, the standard requires disclosure of the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. We applied the five-step method outlined in the ASU to all in-scope revenue streams and elected the modified retrospective implementation method. Implementation of the standard did not have a material impact on our financial position, results of operations or cash flows. Implementation of the standard did not have a significant impact on the measurement or recognition of revenue; therefore, no cumulative adoption adjustment to the opening balance of Retained earnings at the date of initial application was necessary. The additional disclosures required by the ASU are included in Note 1. Compensation - Retirement Benefits: Improving the Presentation of Net Periodic Pension Cost and Net Periodic Post-Retirement Benefit Cost, ASU 2017-07 Effective January 1, 2018, we adopted ASU 2017-07, Compensation – Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Post-Retirement Benefit Cost . The standard requires employers to report the service cost component in the same line item(s) as other compensation costs, and requires the other components of net periodic pension and post-retirement benefit costs to be separately presented in the income statement outside of income from operations. Additionally, only the service cost component may be eligible for capitalization, when applicable. However, all cost components remain eligible for capitalization under FERC regulations. The capitalization of only the service cost component of net periodic pension and post-retirement benefit costs in assets was applied on a prospective basis for the year ended December 31, 2018. Retrospective impact was not material and therefore not adjusted. For our rate-regulated entities, we capitalize the other components of net periodic benefit costs into regulatory assets or regulatory liabilities and maintain a FERC-to-GAAP reporting difference for these capitalized costs. The presentation changes required for net periodic pension and post-retirement costs resulted in offsetting changes to Operating income and Other income. Implementation of the standard did not have a material impact on our financial position, results of operations or cash flows. Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments, ASU 2016-15 Effective January 1, 2018, we adopted ASU 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments (a consensus of the Emerging Issues Task Force). This ASU requires changes in the presentation of certain items, including but not limited to, debt prepayment or debt extinguishment costs, contingent consideration payments made after a business combination, proceeds from the settlement of insurance claims, proceeds from the settlement of corporate-owned life insurance policies and distributions received from equity method investees. We implemented this standard effective January 1, 2018 using the retrospective transition method. This standard had no impact on our financial position, results of operations or cash flows. |
Business Description and Summ_3
Business Description and Summary of Significant Accounting Policies (Tables) | 12 Months Ended |
Dec. 31, 2018 | |
Organization, Consolidation and Presentation of Financial Statements [Abstract] | |
Schedule of Regulatory Assets and Liabilities | We had the following regulatory assets and liabilities as of December 31 (in thousands): 2018 2017 Regulatory assets Loss on reacquired debt (a) $ 1,259 $ 1,534 Deferred taxes on AFUDC (b) 5,020 5,095 Employee benefit plans and related deferred taxes (c) 19,868 19,465 Deferred energy and fuel cost adjustments (a) 20,334 19,602 Deferred taxes on flow through accounting (c) 8,749 7,579 Decommissioning costs (b) 8,196 10,252 Vegetation management (a) 10,366 12,669 Other regulatory assets (a) 1,940 2,507 $ 75,732 $ 78,703 Less current regulatory assets (19,052 ) (18,993 ) Regulatory assets, non-current $ 56,680 $ 59,710 Regulatory liabilities Cost of removal for utility plant (a) $ 52,366 $ 44,056 Employee benefit plans and related deferred taxes (c) 7,518 6,808 Excess deferred income taxes (c) 100,276 97,101 TCJA revenue reserve 2,523 — Other regulatory liabilities (c) 533 890 $ 163,216 $ 148,855 Less current regulatory liabilities (2,574 ) (842 ) Regulatory liabilities, non-current $ 160,642 $ 148,013 ____________________ (a) We are allowed a recovery of costs but we are not allowed a rate of return. (b) In addition to recovery of costs, we are allowed a rate of return. (c) In addition to recovery or repayment of costs, we are allowed a return on a portion of this amount or a reduction in rate base. |
Schedule of Accounts, Notes, Loans and Financing Receivable | Following is a summary of accounts receivable as of December 31 (in thousands): 2018 2017 Accounts receivable, trade $ 16,236 $ 15,994 Unbilled revenue 12,333 13,280 Less Allowance for doubtful accounts (138 ) (224 ) Accounts receivable, net $ 28,431 $ 29,050 |
SEC Schedule, 12-09, Schedule of Valuation and Qualifying Accounts Disclosure [Text Block] | Changes to allowance for doubtful accounts for the years ended December 31, were as follows (in thousands): Balance at beginning of year Additions charged to costs and expenses Deductions charged to costs and expenses Balance at end of year 2018 $ 224 $ 911 $ (997 ) $ 138 2017 $ 157 $ 882 $ (815 ) $ 224 2016 $ 207 $ 644 $ (694 ) $ 157 |
Disaggregation of Revenue | The following table depicts the disaggregation of revenue, including intercompany revenue, from contracts with customers by customer type and timing of revenue recognition. Sales tax and other similar taxes are excluded from revenues. Year ended December 31, 2018 (in thousands) Customer types: Retail $ 197,184 Wholesale 33,687 Market - off-system sales 17,691 Transmission/Other 49,015 Revenue from contracts with customers 297,577 Other revenues 503 Total revenues $ 298,080 Timing of revenue recognition: Services transferred over time $ 297,577 Revenue from contracts with customers $ 297,577 |
Schedule of Accrued Liabilities | The following amounts by major classification are included in Accrued liabilities on the accompanying Balance Sheets as of December 31 (in thousands): 2018 2017 Accrued employee compensation, benefits and withholdings $ 4,206 $ 4,305 Accrued property taxes 6,332 5,930 Accrued income taxes 12,536 17,472 Customer deposits and prepayments 5,204 4,863 Accrued interest 4,627 4,708 Other (none of which is individually significant) 1,288 927 Total accrued liabilities $ 34,193 $ 38,205 |
Property, Plant and Equipment (
Property, Plant and Equipment (Tables) | 12 Months Ended |
Dec. 31, 2018 | |
Property, Plant and Equipment [Abstract] | |
Property, Plant and Equipment | Property, plant and equipment at December 31 consisted of the following (dollars in thousands): 2018 2017 Weighted Weighted Average Average 2018 Useful Life (in years) 2017 Useful Life (in years) Electric plant: Production $ 588,565 46 $ 587,323 46 Transmission 208,610 48 186,045 49 Distribution 394,475 45 375,214 46 Plant acquisition adjustment (a) 4,870 32 4,870 32 General 154,621 28 153,535 32 Total plant-in-service 1,351,141 1,306,987 Construction work in progress 29,904 4,832 Total electric plant 1,381,045 1,311,819 Less accumulated depreciation and amortization (376,160 ) (358,946 ) Electric plant net of accumulated depreciation and amortization $ 1,004,885 $ 952,873 __________________ (a) The plant acquisition adjustment is included in rate base and is being recovered with 12 years remaining. |
Jointly Owned Facilities (Table
Jointly Owned Facilities (Tables) | 12 Months Ended |
Dec. 31, 2018 | |
Jointly Owned Utility Plant, Net Ownership Amount [Abstract] | |
Schedule Of Jointly Owned Facilities | As of December 31, 2018 , our interests in jointly-owned generating facilities and transmission systems were (in thousands): Interest in jointly-owned facilities Plant in Service Construction Work in Progress Accumulated Depreciation Wyodak Plant $ 115,198 $ 384 $ 61,730 Transmission Tie $ 20,855 $ 1,860 $ 6,667 Wygen III $ 140,072 $ 645 $ 22,647 Cheyenne Prairie $ 92,053 $ 69 $ 11,460 |
Long-term Debt (Tables)
Long-term Debt (Tables) | 12 Months Ended |
Dec. 31, 2018 | |
Long-term Debt, Unclassified [Abstract] | |
Schedule of Long-term Debt Instruments | Long-term debt outstanding at December 31 was as follows (in thousands): Interest Rate at Balance Outstanding Due Date December 31, 2018 December 31, 2018 December 31, 2017 First Mortgage Bonds due 2032 August 15, 2032 7.23 % 75,000 75,000 First Mortgage Bonds due 2039 November 1, 2039 6.13 % 180,000 180,000 First Mortgage Bonds due 2044 October 20, 2044 4.43 % 85,000 85,000 Less unamortized debt discount (86 ) (90 ) Series 94A Debt (a) June 1, 2024 1.93 % 2,855 2,855 Less unamortized deferred financing costs (2,734 ) (2,870 ) Long-term Debt 340,035 339,895 ___________________ (a) Variable interest rate at December 31, 2018 . |
Schedule of Maturities of Long-term Debt | Scheduled maturities of our outstanding long-term debt (excluding unamortized discounts and unamortized deferred financing costs) are as follows (in thousands): 2019 $ — 2020 $ — 2021 $ — 2022 $ — 2023 $ — Thereafter $ 342,855 |
Fair Value of Financial Instr_2
Fair Value of Financial Instruments (Tables) | 12 Months Ended |
Dec. 31, 2018 | |
Fair Value Disclosures [Abstract] | |
Fair Value of Financial Instruments | The estimated fair values of our financial instruments at December 31 were as follows (in thousands): 2018 2017 Carrying Value Fair Value Carrying Value Fair Value Cash (a) $ 112 $ 112 $ 16 $ 16 Long-term debt (b) (c) $ 340,035 $ 412,894 $ 339,895 $ 446,978 _______________ (a) The cash fair value approximates carrying value and therefore is classified as Level 1 in the fair value hierarchy. We believe that the market risk arising from cash in a bank account is minimal. (b) Long-term debt is valued based on observable inputs available either directly or indirectly for similar liabilities in active markets and therefore is classified in Level 2 in the fair value hierarchy. (c) Carrying amount of long-term debt is net of deferred financing costs. |
Income Taxes (Tables)
Income Taxes (Tables) | 12 Months Ended |
Dec. 31, 2018 | |
Income Tax Disclosure [Abstract] | |
Schedule of Components of Income Tax Expense (Benefit) | Income tax expense for the years ended December 31 was as follows (in thousands): 2018 2017 2016 Current: Federal $ 5,454 $ 13,124 $ 1,838 Deferred: Federal 5,958 1,004 20,690 Excess deferred tax amortization (740 ) — — $ 5,218 $ 1,004 $ 20,690 Total income tax expense $ 10,672 $ 14,128 $ 22,528 |
Schedule of Deferred Tax Assets and Liabilities | The temporary differences, which gave rise to the net deferred tax liability, for the years ended December 31 were as follows (in thousands): 2018 2017 Deferred tax assets: Employee benefits $ 2,404 $ 3,012 Regulatory liabilities 25,587 24,984 Other 2,317 1,678 Total deferred tax assets 30,308 29,674 Deferred tax liabilities: Accelerated depreciation and other plant related differences (125,594 ) (122,002 ) Regulatory assets (7,147 ) (7,008 ) Employee benefits (2,719 ) (2,595 ) Deferred costs (8,572 ) (8,447 ) Other (285 ) (240 ) Total deferred tax liabilities (144,317 ) (140,292 ) Net deferred tax liability $ (114,009 ) $ (110,618 ) |
Schedule of Effective Income Tax Rate Reconciliation | The effective tax rate differs from the federal statutory rate for the years ended December 31, as follows: 2018 2017 2016 Federal statutory rate 21.0% 35.0% 35.0% Amortization of excess deferred and investment tax credits (1.3) (0.1) (0.4) AFUDC Equity 0.1 (1.0) (0.9) Flow-through adjustments (a) (1.7) (1.8) (0.9) Tax credits — — (0.1) TCJA corporate rate reduction (b) 2.5 (9.2) — Other (1.7) (1.3) 0.6 18.9% 21.6% 33.3% _________________________ (a) Flow-through adjustments related primarily to an accounting method change for tax purposes that allows us to take a current tax deduction for repair costs. We recorded a deferred income tax liability in recognition of the temporary difference created between book and tax treatment and we flowed the tax benefit through to tax expense. (b) On December 22, 2017, the TCJA was signed into law reducing the federal corporate rate from 35% to 21% , effective January 1, 2018. The 2017 effective tax rate reduction reflects the revaluation of deferred income taxes required by the change. During the year ended December 31, 2018, we recorded approximately $0.9 million of additional tax expense associated with changes in the prior estimated impacts of TCJA related items. |
Summary of Deferred Tax Liability Not Recognized | The following table reconciles the total amounts of unrecognized tax benefits, without interest, included in Other deferred credits and other liabilities on the accompanying Balance Sheet (in thousands): 2018 2017 Unrecognized tax benefits at January 1 $ 302 $ 493 Additions for current year tax positions — 13 Additions for prior year tax positions 2 — Reductions for prior year tax positions (55 ) (204 ) Unrecognized tax benefits at December 31 $ 249 $ 302 |
Comprehensive Income (Tables)
Comprehensive Income (Tables) | 12 Months Ended |
Dec. 31, 2018 | |
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] | |
Reclassification out of Accumulated Other Comprehensive Income | The components of the reclassification adjustments for the period, net of tax, included in Other Comprehensive Income were as follows (in thousands): Location on the Statements of Income (Loss) Amounts Reclassified from AOCI 2018 2017 Gains and (losses) on cash flow hedges: Interest rate swaps Interest expense $ 64 $ 64 Income tax Income tax benefit (expense) (13 ) (22 ) Total reclassification adjustments related to cash flow hedges, net of tax $ 51 $ 42 Amortization of defined benefit plans: Actuarial gain (loss) Operations and maintenance $ 103 $ 86 Income tax Income tax benefit (expense) (22 ) (30 ) Total reclassification adjustments related to defined benefit plans, net of tax $ 81 $ 56 |
Schedule of Accumulated Other Comprehensive Income (Loss) | Balances by classification included within Accumulated other comprehensive loss on the accompanying Balance Sheets were as follows (in thousands): Interest Rate Swaps Employee Benefit Plans Total As of December 31, 2017 $ (551 ) $ (707 ) $ (1,258 ) Other comprehensive income (loss) before reclassifications — 235 235 Amounts reclassified from AOCI 51 81 132 As of December 31, 2018 $ (500 ) $ (391 ) $ (891 ) Interest Rate Swaps Employee Benefit Plans Total As of December 31, 2016 $ (593 ) $ (669 ) $ (1,262 ) Other comprehensive income (loss) before reclassifications — (94 ) (94 ) Amounts reclassified from AOCI 42 56 98 As of December 31, 2017 $ (551 ) $ (707 ) $ (1,258 ) |
Employee Benefit Plans (Tables)
Employee Benefit Plans (Tables) | 12 Months Ended |
Dec. 31, 2018 | |
Defined Benefit Plan Disclosure [Line Items] | |
Schedule of Allocation of Plan Assets | The percentages of total plan asset by investment category of our Pension Plan assets at December 31 were as follows: 2018 2017 Equity securities 17 % 26 % Real estate 4 4 Fixed income funds 71 63 Cash and cash equivalents 3 1 Hedge funds 5 6 Total 100 % 100 % |
Schedule of Contribution to Employee Plans | Contributions for the years ended December 31 were as follows (in thousands): 2018 2017 Defined Contribution Plans Company Retirement Contribution $ 876 $ 861 Matching Contributions $ 1,272 $ 1,306 2018 2017 Defined Benefit Plans Defined Benefit Pension Plan $ 1,795 $ 4,000 Non-Pension Defined Benefit Postretirement Healthcare Plans $ 388 $ 348 Supplemental Non-qualified Defined Benefit Plan $ 238 $ 246 |
Schedule of Changes in Projected Benefit Obligations | Benefit Obligations Defined Benefit Pension Plan Supplemental Non-qualified Defined Benefit Plans Non-pension Defined Benefit Postretirement Healthcare Plans As of December 31 (in thousands) 2018 2017 2018 2017 2018 2017 Change in benefit obligation: Projected benefit obligation at beginning of year $ 67,562 $ 64,973 $ 3,418 $ 3,404 $ 5,970 $ 5,843 Service cost 516 545 — — 193 206 Interest cost 2,194 2,341 108 116 179 176 Actuarial loss (gain) (2,878 ) 4,008 (296 ) 144 (889 ) 130 Benefits paid (3,562 ) (3,445 ) (238 ) (246 ) (389 ) (348 ) Plan participants transfer to affiliate (1,913 ) (860 ) — — (129 ) (137 ) Plan participants’ contributions — — — — 120 100 Projected benefit obligation at end of year $ 61,919 $ 67,562 $ 2,992 $ 3,418 $ 5,055 $ 5,970 |
Schedule of Changes in Fair Value of Plan Assets | Employee Benefit Plan Assets Defined Benefit Pension Plan Supplemental Non-qualified Defined Benefit Plans Non-pension Defined Benefit Postretirement Healthcare Plans As of December 31 (in thousands) 2018 2017 2018 2017 2018 2017 Beginning fair value of plan assets $ 59,884 $ 53,888 $ — $ — $ — $ — Investment income (loss) (1,884 ) 6,150 — — — — Employer contributions 1,795 4,000 238 246 268 248 Retiree contributions — — — — 120 100 Benefits paid (3,563 ) (3,445 ) (238 ) (246 ) (388 ) (348 ) Plan participants transfer to affiliate (1,568 ) (709 ) — — — — Ending fair value of plan assets $ 54,664 $ 59,884 $ — $ — $ — $ — |
Schedule of Amounts Recognized in Balance Sheet | The funded status of the plans and amounts recognized in the Balance Sheets at December 31 consist of (in thousands): Defined Benefit Pension Plan Supplemental Non-qualified Defined Benefit Plans Non-pension Defined Benefit Postretirement Healthcare Plans 2018 2017 2018 2017 2018 2017 Regulatory asset $ 19,099 $ 18,998 $ — $ — $ — $ — Current liability $ — $ — $ 230 $ 245 $ 466 $ 534 Non-current liability $ 7,255 $ 7,676 $ 2,762 $ 3,173 $ 4,589 $ 5,436 Regulatory liability $ — $ — $ — $ — $ 2,441 $ 1,758 |
Schedule of Accumulated and Projected Benefit Obligations | Accumulated Benefit Obligation Defined Benefit Pension Plan Supplemental Non-pension Defined Benefit Postretirement Healthcare Plans As of December 31 (in thousands) 2018 2017 2018 2017 2018 2017 Accumulated benefit obligation $ 59,987 $ 64,782 $ 2,992 $ 3,418 $ 5,055 $ 5,970 |
Schedule of Net Benefit Costs | Components of Net Periodic Expense Net periodic expense consisted of the following for the year ended December 31 (in thousands): Defined Benefit Pension Plan Supplemental Non-pension Defined Benefit Postretirement Healthcare Plan 2018 2017 2016 2018 2017 2016 2018 2017 2016 Service cost $ 516 $ 545 $ 606 $ — $ — $ — $ 193 $ 206 $ 204 Interest cost 2,194 2,341 2,499 108 116 122 179 176 187 Expected return on assets (3,545 ) (3,591 ) (3,632 ) — — — — — — Amortization of prior service cost (credits) 43 43 43 — — — (336 ) (336 ) (337 ) Recognized net actuarial loss (gain) 2,063 1,230 1,995 103 87 82 — — — Net periodic expense $ 1,271 $ 568 $ 1,511 $ 211 $ 203 $ 204 $ 36 $ 46 $ 54 |
Schedule of Net Periodic Benefit Cost Not yet Recognized | For defined benefit plans, amounts included in AOCI, after-tax, that have not yet been recognized as components of net periodic benefit cost at December 31 were as follows (in thousands): Defined Benefit Pension Plan Supplemental Non-qualified Defined Benefit Plans Non-pension Defined Benefit Postretirement Healthcare Plan 2018 2017 2018 2017 2018 2017 Net (gain) loss $ — $ — $ 391 $ 707 $ — $ — Total AOCI $ — $ — $ 391 $ 707 $ — $ — |
Schedule of Assumptions Used | Assumptions Defined Benefit Pension Plan Supplemental Non-qualified Defined Benefit Plans Non-pension Defined Benefit Postretirement Healthcare Plan 2018 2017 2016 2018 2017 2016 2018 2017 2016 Weighted-average assumptions used to determine benefit obligations: Discount rate 4.40 % 3.71 % 4.27 % 4.30 % 3.62 % 4.12 % 4.28 % 3.60 % 3.84 % Rate of increase in compensation levels 3.52 % 3.43 % 3.47 % N/A N/A N/A N/A N/A N/A Weighted-average assumptions used to determine net periodic benefit cost for plan year: Discount rate (a) 3.71 % 4.27 % 4.63 % 3.62 % 4.12 % 4.29 % 3.60 % 3.84 % 4.03 % Expected long-term rate of return on assets (b) 6.25 % 6.75 % 6.75 % N/A N/A N/A 3.93 % N/A N/A Rate of increase in compensation levels 3.43 % 3.47 % 3.57 % N/A N/A N/A N/A N/A N/A _____________________________ (a) The estimated discount rate for the Defined Benefit Pension Plan is 4.40% for the calculation of the 2019 net periodic pension costs. (b) The expected rate of return on plan assets is 6.00% for the calculation of the 2019 net periodic pension cost. |
Schedule of Health Care Cost Trend Rates | The healthcare benefit obligation was determined at December 31 as follows: 2018 2017 Trend Rate - Medical Pre-65 for next year 6.70 % 7.00 % Pre-65 Ultimate trend rate 4.50 % 4.50 % Trend Year 2027 2027 Post-65 for next year 4.94 % 5.00 % Post-65 Ultimate trend rate 4.50 % 4.50 % Trend Year 2026 2026 |
Schedule of Expected Benefit Payments | The following benefit payments, which reflect future service, are expected to be paid (in thousands): Defined Benefit Pension Plan Supplemental Non-qualified Defined Benefit Plans Non-Pension Defined Benefit Postretirement Healthcare Plan 2019 $ 3,660 $ 230 $ 466 2020 $ 3,774 $ 227 $ 534 2021 $ 3,924 $ 322 $ 566 2022 $ 4,031 $ 319 $ 577 2023 $ 4,102 $ 315 $ 554 2024-2028 $ 20,759 $ 1,274 $ 2,243 |
Defined Benefit Pension Plan | |
Defined Benefit Plan Disclosure [Line Items] | |
Schedule of Allocation of Plan Assets | The following tables set forth, by level within the fair value hierarchy, the assets that were accounted for at fair value on a recurring basis (in thousands): Pension Plan December 31, 2018 Level 1 Level 2 Level 3 Total Investments Measured at Fair Value NAV (a) Total Investments AXA Equitable General Fixed Income $ — $ 261 $ — $ 261 $ — $ 261 Common Collective Trust - Cash and Cash Equivalents — 1,388 — 1,388 — 1,388 Common Collective Trust - Equity — 9,436 — 9,436 — 9,436 Common Collective Trust - Fixed Income — 39,047 — 39,047 — 39,047 Common Collective Trust - Real Estate — 9 — 9 1,896 1,905 Hedge Funds — — — — 2,627 2,627 Total investments measured at fair value $ — $ 50,141 $ — $ 50,141 $ 4,523 $ 54,664 Pension Plan December 31, 2017 Level 1 Level 2 Level 3 Total Investments Measured at Fair Value NAV (a) Total Investments AXA Equitable General Fixed Income $ — $ 184 $ — $ 184 $ — $ 184 Common Collective Trust - Cash and Cash Equivalents — 314 — 314 — 314 Common Collective Trust - Equity — 15,749 — 15,749 — 15,749 Common Collective Trust - Fixed Income — 37,732 — 37,732 — 37,732 Common Collective Trust - Real Estate — 249 — 249 2,258 2,507 Hedge Funds — — — — 3,398 3,398 Total investments measured at fair value $ — $ 54,228 $ — $ 54,228 $ 5,656 $ 59,884 ________________________ (a) Certain investments that are measured at fair value using Net Asset Value “NAV” per share (or its equivalent) for practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in these tables for these investments are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the reconciliation of changes in the plan’s benefit obligations and fair value of plan assets above. |
Related-Party Transactions (Tab
Related-Party Transactions (Tables) | 12 Months Ended |
Dec. 31, 2018 | |
Related Party Transactions [Abstract] | |
Schedule of Related Party Accounts Receivable and Payable | We have accounts receivable and accounts payable balances related to transactions with other BHC subsidiaries. These balances as of December 31 were as follows (in thousands): 2018 2017 Accounts receivable from affiliates $ 8,119 $ 5,664 Accounts payable to affiliates $ 25,804 $ 25,653 |
Schedule of Related Party Notes and Associated Interest Income Expense | We had the following balances with the Utility Money Pool as of December 31 (in thousands): 2018 2017 Money pool notes payable $ 38,690 $ 13,397 |
Schedule of Related Party Interest Income Expense | Interest income relating to the Utility Money Pool for the years ended December 31, was as follows (in thousands): 2018 2017 2016 Interest income (expense) $ (401 ) $ 272 $ 1,047 |
Schedule of Revenues and Purchases from Related Parties | We had the following related-party transactions for the years ended December 31 included in the corresponding captions in the accompanying Statements of Income: 2018 2017 2016 (in thousands) Revenues: Energy sold to Cheyenne Light $ 2,064 $ 2,481 $ 2,440 Rent from electric properties $ 3,634 $ 3,680 $ 5,046 Horizon Point shared facility revenue $ 11,211 $ 1,420 $ — Fuel and purchased power: Purchases of coal from WRDC $ 17,532 $ 15,948 $ 16,227 Purchase of excess energy from Cheyenne Light $ 511 $ 601 $ 252 Purchase of renewable wind energy from Cheyenne Light - Happy Jack $ 1,942 $ 1,924 $ 1,918 Purchase of renewable wind energy from Cheyenne Light - Silver Sage $ 3,586 $ 3,290 $ 3,300 Gas transportation service agreement with Cheyenne Light for firm and interruptible gas transportation $ 364 $ 393 $ 399 |
Schedule of Related Party Corporate Support | We had the following corporate support for the years ended December 31: 2018 2017 2016 (in thousands) Corporate support services and fees from Parent, Black Hills Service Company and Black Hills Utility Holdings $ 34,578 $ 27,869 $ 25,748 |
Supplemental Cash Flow Inform_2
Supplemental Cash Flow Information (Tables) | 12 Months Ended |
Dec. 31, 2018 | |
Supplemental Cash Flow Information [Abstract] | |
Schedule of Cash Flow, Supplemental Disclosures | Years ended December 31, 2018 2017 2016 (in thousands) Non-cash investing and financing activities - Property, plant and equipment acquired with accrued liabilities $ 15,180 $ 6,565 $ 5,521 Non-cash decrease to money pool note receivable, net $ (36,000 ) $ (42,000 ) $ (52,500 ) Non-cash dividend to Parent $ 36,000 $ 42,000 $ 52,500 Cash (paid) refunded during the period for - Interest (net of amounts capitalized) $ (21,988 ) $ (21,517 ) $ (21,320 ) Income taxes (paid) refunded $ (10,394 ) $ (12,719 ) $ — |
Commitment and Contingencies (T
Commitment and Contingencies (Tables) | 12 Months Ended |
Dec. 31, 2018 | |
Commitments and Contingencies Disclosure [Abstract] | |
Long-term Purchase Commitment | Costs incurred under these agreements were as follows for the years ended December 31 (in thousands): Contract Contract Type 2018 2017 2016 PacifiCorp Electric capacity and energy $ 13,681 $ 13,218 $ 12,221 PacifiCorp Transmission access $ 1,742 $ 1,671 $ 1,428 Thunder Creek Gas transport capacity $ 633 $ 633 $ 633 Platte River Power Authority Wind energy $ 223 $ — $ — |
Unrecorded Unconditional Purchase Obligations Disclosure | The following is a schedule of future minimum payments required under power purchase, transmission services, land and facility operating leases, and gas supply agreements (in thousands): 2019 $ 8,050 2020 $ 7,693 2021 $ 7,059 2022 $ 7,059 2023 $ 7,056 Thereafter $ 21,947 |
Quarterly Historical Data (Un_2
Quarterly Historical Data (Unaudited) (Tables) | 12 Months Ended |
Dec. 31, 2018 | |
Selected Quarterly Financial Information [Abstract] | |
Schedule of Quarterly Financial Information | The following table sets forth selected unaudited historical operating results data for each quarter (in thousands): First Quarter Second Quarter Third Quarter Fourth Quarter 2018 Revenues $ 73,815 $ 70,676 $ 78,067 $ 75,522 Operating income $ 20,364 $ 19,495 $ 21,428 $ 17,048 Net income $ 11,760 $ 11,125 $ 13,317 $ 9,443 2017 Revenues $ 73,794 $ 66,053 $ 73,938 $ 74,648 Operating income $ 23,376 $ 17,712 $ 23,698 $ 19,040 Net income $ 12,570 $ 9,287 $ 13,826 $ 15,615 |
Business Description and Summ_4
Business Description and Summary of Significant Accounting Policies: Cash Equivalents (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017 |
Organization, Consolidation and Presentation of Financial Statements [Abstract] | ||
Cash Equivalents | $ 0 | $ 0 |
Business Description and Summ_5
Business Description and Summary of Significant Accounting Policies: Regulatory Assets and Liabilities (Details) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2018 | Dec. 31, 2017 | |
Schedule Of Regulatory Assets And Liabilities [Line Items] | ||
Regulatory Assets | $ 75,732 | $ 78,703 |
Regulatory Assets, Current | (19,052) | (18,993) |
Regulatory assets, non-current | 56,680 | 59,710 |
Regulatory Liabilities | 163,216 | 148,855 |
Regulatory Liability, Current | (2,574) | (842) |
Regulatory liabilities, non-current | 160,642 | 148,013 |
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit) | 103,000 | |
Cost of removal for utility plant | ||
Schedule Of Regulatory Assets And Liabilities [Line Items] | ||
Regulatory Liabilities | 52,366 | 44,056 |
Employee benefit plans | ||
Schedule Of Regulatory Assets And Liabilities [Line Items] | ||
Regulatory Liabilities | 7,518 | 6,808 |
Deferred Income Tax Charges | ||
Schedule Of Regulatory Assets And Liabilities [Line Items] | ||
Regulatory Liabilities | 100,276 | 97,101 |
Tax Cuts and Jobs Act of 2017, Provisional Income Tax Expense (Benefit) | 100,000 | |
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit) | 97,000 | |
Revenue Subject to Refund | ||
Schedule Of Regulatory Assets And Liabilities [Line Items] | ||
Regulatory Liabilities | 2,523 | 0 |
Other regulatory liabilities | ||
Schedule Of Regulatory Assets And Liabilities [Line Items] | ||
Regulatory Liabilities | 533 | 890 |
Unamortized loss on reacquired debt | ||
Schedule Of Regulatory Assets And Liabilities [Line Items] | ||
Regulatory Assets | 1,259 | 1,534 |
Allowance for Funds Used During Construction | ||
Schedule Of Regulatory Assets And Liabilities [Line Items] | ||
Regulatory Assets | 5,020 | 5,095 |
Employee benefit plans | ||
Schedule Of Regulatory Assets And Liabilities [Line Items] | ||
Regulatory Assets | 19,868 | 19,465 |
Deferred energy costs | ||
Schedule Of Regulatory Assets And Liabilities [Line Items] | ||
Regulatory Assets | 20,334 | 19,602 |
Flow through accounting | ||
Schedule Of Regulatory Assets And Liabilities [Line Items] | ||
Regulatory Assets | 8,749 | 7,579 |
Decommissioning costs | ||
Schedule Of Regulatory Assets And Liabilities [Line Items] | ||
Regulatory Assets | 8,196 | 10,252 |
Vegetation Management | ||
Schedule Of Regulatory Assets And Liabilities [Line Items] | ||
Regulatory Assets | 10,366 | 12,669 |
Other Regulatory Assets | ||
Schedule Of Regulatory Assets And Liabilities [Line Items] | ||
Regulatory Assets | $ 1,940 | $ 2,507 |
Business Description and Summ_6
Business Description and Summary of Significant Accounting Policies: Accounts Receivable (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017 |
Accounts, Notes, Loans and Financing Receivable [Line Items] | ||
Less Allowance for doubtful accounts | $ (138) | $ (224) |
Accounts receivable, net | 28,431 | 29,050 |
Billed Revenues | ||
Accounts, Notes, Loans and Financing Receivable [Line Items] | ||
Accounts receivable, trade | 16,236 | 15,994 |
Unbilled Revenues | ||
Accounts, Notes, Loans and Financing Receivable [Line Items] | ||
Accounts receivable, trade | $ 12,333 | $ 13,280 |
Business Description and Summ_7
Business Description and Summary of Significant Accounting Policies: Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] | |||
Allowance for doubtful accounts, balance at beginning of year | $ 224 | $ 157 | $ 207 |
Additions charged to costs and expenses | 911 | 882 | 644 |
Deductions charged to costs and expenses | (997) | (815) | (694) |
Allowance for doubtful accounts, balance at end of year | $ 138 | $ 224 | $ 157 |
Business Description and Summ_8
Business Description and Summary of Significant Accounting Policies: Revenue (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended | |||||||||
Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Disaggregation of Revenue [Line Items] | |||||||||||
Revenue from Contract with Customer, Excluding Assessed Tax | $ 297,577 | ||||||||||
Regulated Operating Revenue, Other | 503 | ||||||||||
Revenue | $ 75,522 | $ 78,067 | $ 70,676 | $ 73,815 | $ 74,648 | $ 73,938 | $ 66,053 | $ 73,794 | 298,080 | $ 288,433 | $ 267,632 |
Significant Judgments and Estimates [Abstract] | |||||||||||
Revenue Refunded To Customers As A Result Of The TCJA Tax Benefits | 7,600 | ||||||||||
Regulatory Liabilities | 163,216 | 148,855 | 163,216 | 148,855 | |||||||
Revenue Subject to Refund | |||||||||||
Significant Judgments and Estimates [Abstract] | |||||||||||
Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount | 10,000 | ||||||||||
Revenue Refunded To Customers As A Result Of The TCJA Tax Benefits | 900 | ||||||||||
Regulatory Liabilities | $ 2,523 | $ 0 | 2,523 | $ 0 | |||||||
Transferred over Time | |||||||||||
Disaggregation of Revenue [Line Items] | |||||||||||
Revenue from Contract with Customer, Excluding Assessed Tax | 297,577 | ||||||||||
Regulated Utility Retail | |||||||||||
Disaggregation of Revenue [Line Items] | |||||||||||
Revenue from Contract with Customer, Excluding Assessed Tax | 197,184 | ||||||||||
Regulated Utility Wholesale | |||||||||||
Disaggregation of Revenue [Line Items] | |||||||||||
Revenue from Contract with Customer, Excluding Assessed Tax | 33,687 | ||||||||||
Regulated Utility Market Off-System Sales | |||||||||||
Disaggregation of Revenue [Line Items] | |||||||||||
Revenue from Contract with Customer, Excluding Assessed Tax | 17,691 | ||||||||||
Regulated Utility Transmission | |||||||||||
Disaggregation of Revenue [Line Items] | |||||||||||
Revenue from Contract with Customer, Excluding Assessed Tax | $ 49,015 |
Business Description and Summ_9
Business Description and Summary of Significant Accounting Policies: Property, Plant and Equipment (Details) | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Organization, Consolidation and Presentation of Financial Statements [Abstract] | |||
Composite Depreciation Rate for Plants in Service | 2.30% | 2.10% | 2.20% |
Business Description and Sum_10
Business Description and Summary of Significant Accounting Policies: Accrued Liabilities (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017 |
Organization, Consolidation and Presentation of Financial Statements [Abstract] | ||
Accrued employee compensation, benefits and withholdings | $ 4,206 | $ 4,305 |
Accrued property taxes | 6,332 | 5,930 |
Accrued income taxes | 12,536 | 17,472 |
Customer deposits and prepayments | 5,204 | 4,863 |
Accrued interest | 4,627 | 4,708 |
Other (none of which is individually significant) | 1,288 | 927 |
Total accrued liabilities | $ 34,193 | $ 38,205 |
Business Description and Sum_11
Business Description and Summary of Significant Accounting Policies: Leases (Details) - Subsequent Event $ in Millions | Jan. 01, 2019USD ($) |
Subsequent Event [Line Items] | |
Operating Lease, Right-of-Use Asset | $ 14 |
Operating Lease, Liability | $ 14 |
Business Description and Sum_12
Business Description and Summary of Significant Accounting Policies: Revenue from Contracts with Customers (Details) | Dec. 31, 2018USD ($) |
Accounting Standards Update 2014-09 | |
Disaggregation of Revenue [Line Items] | |
Cumulative Effect of New Accounting Principle in Period of Adoption | $ 0 |
Property, Plant and Equipment_2
Property, Plant and Equipment (Details) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2018 | Dec. 31, 2017 | |
Public Utilities, Property, Plant and Equipment, Net [Abstract] | ||
Total plant-in-service | $ 1,351,141 | $ 1,306,987 |
Construction work in progress | 29,904 | 4,832 |
Total electric plant | 1,381,045 | 1,311,819 |
Less accumulated depreciation and amortization | (376,160) | (358,946) |
Electric plant net of accumulated depreciation and amortization | $ 1,004,885 | 952,873 |
Remaining amortization period | 12 years | |
Electric Production | ||
Public Utilities, Property, Plant and Equipment, Net [Abstract] | ||
Production | $ 588,565 | $ 587,323 |
Electric Production | Weighted average useful life | ||
Public Utilities, Property, Plant and Equipment, Net [Abstract] | ||
Useful Life (in years) | 46 years | 46 years |
Electric Transmission | ||
Public Utilities, Property, Plant and Equipment, Net [Abstract] | ||
Transmission | $ 208,610 | $ 186,045 |
Electric Transmission | Weighted average useful life | ||
Public Utilities, Property, Plant and Equipment, Net [Abstract] | ||
Useful Life (in years) | 48 years | 49 years |
Electric Distribution | ||
Public Utilities, Property, Plant and Equipment, Net [Abstract] | ||
Distribution | $ 394,475 | $ 375,214 |
Electric Distribution | Weighted average useful life | ||
Public Utilities, Property, Plant and Equipment, Net [Abstract] | ||
Useful Life (in years) | 45 years | 46 years |
Plant Acquisition Adjustment | ||
Public Utilities, Property, Plant and Equipment, Net [Abstract] | ||
Plant acquisition adjustment | $ 4,870 | $ 4,870 |
Plant Acquisition Adjustment | Weighted average useful life | ||
Public Utilities, Property, Plant and Equipment, Net [Abstract] | ||
Useful Life (in years) | 32 years | 32 years |
General | ||
Public Utilities, Property, Plant and Equipment, Net [Abstract] | ||
General | $ 154,621 | $ 153,535 |
General | Weighted average useful life | ||
Public Utilities, Property, Plant and Equipment, Net [Abstract] | ||
Useful Life (in years) | 28 years | 32 years |
Jointly Owned Facilities (Detai
Jointly Owned Facilities (Details) $ in Thousands | 12 Months Ended |
Dec. 31, 2018USD ($)MW | |
Wyodak Plant | |
Jointly Owned Utility Plant Interests [Line Items] | |
Proportionate Ownership Percentage | 20.00% |
Plant in Service | $ 115,198 |
Construction Work in Progress | 384 |
Accumulated Depreciation | $ 61,730 |
Transmission Tie | |
Jointly Owned Utility Plant Interests [Line Items] | |
Proportionate Ownership Percentage | 35.00% |
Utility Plant, Megawatt Capacity | MW | 400 |
Plant in Service | $ 20,855 |
Construction Work in Progress | 1,860 |
Accumulated Depreciation | $ 6,667 |
Transmission Tie | West to East Transmission Tie | |
Jointly Owned Utility Plant Interests [Line Items] | |
Utility Plant, Megawatt Capacity | MW | 200 |
Transmission Tie | East to West Transmission Tie | |
Jointly Owned Utility Plant Interests [Line Items] | |
Utility Plant, Megawatt Capacity | MW | 200 |
Wygen III Generating Facility | |
Jointly Owned Utility Plant Interests [Line Items] | |
Proportionate Ownership Percentage | 52.00% |
Plant in Service | $ 140,072 |
Construction Work in Progress | 645 |
Accumulated Depreciation | $ 22,647 |
Cheyenne Prairie | |
Jointly Owned Utility Plant Interests [Line Items] | |
Electric Generation Capacity, Megawatts | MW | 95 |
Plant in Service | $ 92,053 |
Construction Work in Progress | 69 |
Accumulated Depreciation | $ 11,460 |
South Dakota Electric Portion | Cheyenne Prairie | |
Jointly Owned Utility Plant Interests [Line Items] | |
Electric Generation Capacity, Megawatts | MW | 55 |
Wyoming Electric Portion | Cheyenne Prairie | Wyoming Electric | |
Jointly Owned Utility Plant Interests [Line Items] | |
Electric Generation Capacity, Megawatts | MW | 40 |
Long-term Debt (Details)
Long-term Debt (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Debt Instrument [Line Items] | |||
Unamortized Discount | $ (86) | $ (90) | |
Less unamortized deferred financing costs | (2,734) | (2,870) | |
Long-term Debt | 340,035 | 339,895 | |
Amortization of Financing Costs | $ 100 | 100 | $ 100 |
First Mortgage Bonds Due 2032 | |||
Debt Instrument [Line Items] | |||
Interest Rate, Stated Percentage | 7.23% | ||
Long-term Debt, Gross | $ 75,000 | 75,000 | |
First Mortgage Bonds Due 2039 | |||
Debt Instrument [Line Items] | |||
Interest Rate, Stated Percentage | 6.125% | ||
Long-term Debt, Gross | $ 180,000 | 180,000 | |
First Mortgage Bonds Due 2044 | |||
Debt Instrument [Line Items] | |||
Interest Rate, Stated Percentage | 4.43% | ||
Long-term Debt, Gross | $ 85,000 | 85,000 | |
Bonds Due 2024 | |||
Debt Instrument [Line Items] | |||
Variable Interest, Percentage Rate | 1.93% | ||
Long-term Debt, Gross | $ 2,855 | $ 2,855 |
Long-term Debt_ Schedule of Mat
Long-term Debt: Schedule of Maturities of Long-term Debt (Details) $ in Thousands | Dec. 31, 2018USD ($) |
Long-term Debt, Unclassified [Abstract] | |
2,019 | $ 0 |
2,020 | 0 |
2,021 | 0 |
2,022 | 0 |
2,023 | 0 |
Thereafter | $ 342,855 |
Fair Value of Financial Instr_3
Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||||
Cash and cash equivalents, at carrying value | $ 112 | $ 16 | $ 234 | $ 297 |
Long-term debt, at carrying value | 340,035 | 339,895 | ||
Carrying Value | ||||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||||
Cash and cash equivalents, at carrying value | 112 | 16 | ||
Long-term debt, at carrying value | 340,035 | 339,895 | ||
Fair Value | ||||
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||||
Cash and cash equivalents, at fair value | 112 | 16 | ||
Long-term debt, at fair value | $ 412,894 | $ 446,978 |
Income Taxes_ TCJA (Details)
Income Taxes: TCJA (Details) - USD ($) $ in Millions | 12 Months Ended | |
Dec. 31, 2018 | Dec. 31, 2017 | |
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit) | $ 103 | |
Revenue Refunded To Customers As A Result Of The TCJA Tax Benefits | $ 7.6 | |
Deferred Income Tax Charges | ||
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit) | $ 97 | |
Tax Cuts and Jobs Act of 2017, Provisional Income Tax Expense (Benefit) | 100 | |
Revenue Subject to Refund | ||
Revenue Refunded To Customers As A Result Of The TCJA Tax Benefits | $ 0.9 |
Income Taxes_ Current and Defer
Income Taxes: Current and Deferred Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Income Tax Disclosure [Abstract] | |||
Current: | $ 5,454 | $ 13,124 | $ 1,838 |
Deferred: | 5,218 | 1,004 | 20,690 |
Deferred Federal Income Tax Expense | 5,958 | 1,004 | 20,690 |
Excess Deferred Amortization | (740) | 0 | 0 |
Total income tax expense | $ 10,672 | $ 14,128 | $ 22,528 |
Income Taxes_ Deferred Income T
Income Taxes: Deferred Income Tax Assets and Liabilities (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017 |
Components of Deferred Tax Assets [Abstract] | ||
Employee benefits | $ 2,404 | $ 3,012 |
Regulatory liabilities | 25,587 | 24,984 |
Other | 2,317 | 1,678 |
Total deferred tax assets | 30,308 | 29,674 |
Components of Deferred Tax Liabilities [Abstract] | ||
Accelerated depreciation and other plant related differences | (125,594) | (122,002) |
Regulatory assets | (7,147) | (7,008) |
Employee benefits | (2,719) | (2,595) |
Deferred costs | (8,572) | (8,447) |
Other | (285) | (240) |
Total deferred tax liabilities | (144,317) | (140,292) |
Net deferred tax liability | $ (114,009) | $ (110,618) |
Income Taxes_ Effective Tax Rat
Income Taxes: Effective Tax Rate Differences from Statutory Tax Rates (Details) - USD ($) $ in Millions | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Income Tax Disclosure [Abstract] | |||
Federal statutory rate | 21.00% | 35.00% | 35.00% |
Amortization of excess deferred and investment tax credits | (1.30%) | (0.10%) | (0.40%) |
AFUDC Equity | 0.10% | (1.00%) | (0.90%) |
Flow through adjustments, percent | (1.70%) | (1.80%) | (0.90%) |
Tax credits | (0.00%) | (0.00%) | (0.10%) |
Tax reform | 2.50% | (9.20%) | 0.00% |
Other | (1.70%) | (1.30%) | 0.60% |
Effective Income Tax Rate | 18.90% | 21.60% | 33.30% |
Additional tax expense associated with TCJA related items | $ 0.9 |
Income Taxes_ Reconciliation of
Income Taxes: Reconciliation of unrecognized tax benefits (Details) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2018 | Dec. 31, 2017 | |
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] | ||
Beginning of Period | $ 302 | $ 493 |
Additions for current year tax positions | 0 | 13 |
Additions for prior year tax positions | 2 | 0 |
Reductions for prior year tax positions | (55) | (204) |
End of Period | $ 249 | $ 302 |
Comprehensive Income_ Other Com
Comprehensive Income: Other Comprehensive Income (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended | |||||||||
Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items] | |||||||||||
Interest expense | $ 22,545 | $ 22,421 | $ 22,908 | ||||||||
Income tax benefit (expense) | 10,672 | 14,128 | 22,528 | ||||||||
Net income | $ 9,443 | $ 13,317 | $ 11,125 | $ 11,760 | $ 15,615 | $ 13,826 | $ 9,287 | $ 12,570 | 45,645 | 51,298 | $ 45,138 |
First Mortgage Bonds Due 2032 | |||||||||||
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items] | |||||||||||
Derivative, Notional Amount | 50,000 | 50,000 | |||||||||
Realized Loss Included Accumulated Other Comprehensive Income (Loss) | $ (1,800) | (1,800) | |||||||||
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges | Reclassification out of Accumulated Other Comprehensive Income | |||||||||||
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items] | |||||||||||
Income tax benefit (expense) | (13) | (22) | |||||||||
Net income | 51 | 42 | |||||||||
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges | Reclassification out of Accumulated Other Comprehensive Income | Interest Rate Contract | |||||||||||
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items] | |||||||||||
Interest expense | 64 | 64 | |||||||||
Accumulated Defined Benefit Plans Adjustment, Net Unamortized Gain (Loss) | Reclassification out of Accumulated Other Comprehensive Income | |||||||||||
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items] | |||||||||||
Utilities Operating Expense, Maintenance, Operations, and Other Costs and Expenses | 103 | 86 | |||||||||
Accumulated Defined Benefit Plans Adjustment | Reclassification out of Accumulated Other Comprehensive Income | |||||||||||
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items] | |||||||||||
Income tax benefit (expense) | (22) | (30) | |||||||||
Net income | $ 81 | $ 56 |
Comprehensive Income_ Accumulat
Comprehensive Income: Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2018 | Dec. 31, 2017 | |
Accumulated Other Comprehensive Income (Loss) [Roll Forward] | ||
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start | $ (1,258) | $ (1,262) |
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End | (891) | (1,258) |
Interest Rate Swaps, Cash Flow Hedges, AOCI | Interest Rate Swaps | ||
Accumulated Other Comprehensive Income (Loss) [Roll Forward] | ||
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start | (551) | (593) |
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax | 0 | 0 |
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End | (500) | (551) |
Employee Benefit Plans, AOCI | ||
Accumulated Other Comprehensive Income (Loss) [Roll Forward] | ||
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start | (707) | (669) |
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax | 235 | (94) |
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End | (391) | (707) |
Accumulated Other Comprehensive Income (Loss) | ||
Accumulated Other Comprehensive Income (Loss) [Roll Forward] | ||
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax | 235 | (94) |
Reclassification out of Accumulated Other Comprehensive Income | Interest Rate Swaps, Cash Flow Hedges, AOCI | Interest Rate Swaps | ||
Accumulated Other Comprehensive Income (Loss) [Roll Forward] | ||
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | 51 | 42 |
Reclassification out of Accumulated Other Comprehensive Income | Employee Benefit Plans, AOCI | ||
Accumulated Other Comprehensive Income (Loss) [Roll Forward] | ||
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | 81 | 56 |
Reclassification out of Accumulated Other Comprehensive Income | Accumulated Other Comprehensive Income (Loss) | ||
Accumulated Other Comprehensive Income (Loss) [Roll Forward] | ||
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | $ 132 | $ 98 |
Employee Benefit Plans_ Narrati
Employee Benefit Plans: Narrative (Details) | 12 Months Ended | |
Dec. 31, 2018 | Dec. 31, 2017 | |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Maximum Annual Contribution Per Employee, Percent | 50.00% | |
Employers Matching Contribution, Annual Vesting Percentage | 20.00% | |
Defined Contribution Plan, Employee Vesting Period | 5 years | |
Target Plan Asset Allocations, percent | 100.00% | 100.00% |
Equity Securities | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Target Plan Asset Allocations, percent | 17.00% | 26.00% |
Fixed Income Funds | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Target Plan Asset Allocations, percent | 71.00% | 63.00% |
Minimum | Defined Benefit Pension Plan | Equity Securities | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Target Plan Asset Allocations, percent | 29.00% | |
Minimum | Defined Benefit Pension Plan | Fixed Income Funds | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Target Plan Asset Allocations, percent | 63.00% | |
Maximum | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Employers Matching Contribution, Annual Vesting Percentage | 100.00% | |
Maximum | Defined Benefit Pension Plan | Equity Securities | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Target Plan Asset Allocations, percent | 37.00% | |
Maximum | Defined Benefit Pension Plan | Fixed Income Funds | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Target Plan Asset Allocations, percent | 71.00% |
Employee Benefit Plans_ Plan As
Employee Benefit Plans: Plan Assets Allocation (Details) | Dec. 31, 2018 | Dec. 31, 2017 |
Defined Benefit Plan Disclosure [Line Items] | ||
Target Plan Asset Allocations, percent | 100.00% | 100.00% |
Equity Securities | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Target Plan Asset Allocations, percent | 17.00% | 26.00% |
Real Estate | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Target Plan Asset Allocations, percent | 4.00% | 4.00% |
Fixed Income Funds | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Target Plan Asset Allocations, percent | 71.00% | 63.00% |
Cash and Cash Equivalents | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Target Plan Asset Allocations, percent | 3.00% | 1.00% |
Hedge Funds | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Target Plan Asset Allocations, percent | 5.00% | 6.00% |
Employee Benefit Plans_ Plan Co
Employee Benefit Plans: Plan Contributions (Details) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2018 | Dec. 31, 2017 | |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year | $ 1,800 | |
Defined Benefit Pension Plan | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Defined Benefit Pension Plan - Employer contributions | 1,795 | $ 4,000 |
Non-pension Defined Benefit Postretirement Healthcare Plan | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Defined Benefit Pension Plan - Employer contributions | 268 | 248 |
Defined Benefit Plans - Other, Employer Contributions | 388 | 348 |
Supplemental Non-qualified Defined Benefit Retirement Plans | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Defined Benefit Pension Plan - Employer contributions | 238 | 246 |
Defined Benefit Plans - Other, Employer Contributions | 238 | 246 |
Company Retirement Contribution | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Defined Contribution Plans, Contributions by Employer | 876 | 861 |
Matching Contributions | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Defined Contribution Plans, Contributions by Employer | $ 1,272 | $ 1,306 |
Employee Benefit Plans_ Fair Va
Employee Benefit Plans: Fair Value Measurements (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Minimum | Hedge Funds | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period | 10 days | ||
Maximum | Hedge Funds | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period | 45 days | ||
Hedge Funds | Minimum | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Percentage Of Monthly Redemption | 20.00% | ||
Hedge Funds | Maximum | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Percentage Of Quarterly Redemption | 100.00% | ||
Defined Benefit Pension Plan | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | $ 54,664 | $ 59,884 | $ 53,888 |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 54,664 | 59,884 | |
Defined Benefit Plan, Fair Value of Plan Assets, Excluding Net Asset Value investments | 50,141 | 54,228 | |
Defined Benefit Plan, Alternative Investments, Fair Value Of Plan Assets | 4,523 | 5,656 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fixed Income Funds | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 261 | 184 | |
Defined Benefit Plan, Fair Value of Plan Assets, Excluding Net Asset Value investments | 261 | 184 | |
Defined Benefit Plan, Alternative Investments, Fair Value Of Plan Assets | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Common Collective Trust, Cash And Cash Equivalents | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 1,388 | 314 | |
Defined Benefit Plan, Fair Value of Plan Assets, Excluding Net Asset Value investments | 1,388 | 314 | |
Defined Benefit Plan, Alternative Investments, Fair Value Of Plan Assets | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Common Collective Trust - Equity | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 9,436 | 15,749 | |
Defined Benefit Plan, Fair Value of Plan Assets, Excluding Net Asset Value investments | 9,436 | 15,749 | |
Defined Benefit Plan, Alternative Investments, Fair Value Of Plan Assets | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Common Collective Trust - Fixed Income | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 39,047 | 37,732 | |
Defined Benefit Plan, Fair Value of Plan Assets, Excluding Net Asset Value investments | 39,047 | 37,732 | |
Defined Benefit Plan, Alternative Investments, Fair Value Of Plan Assets | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Common Collective Trust - Real Estate | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 1,905 | 2,507 | |
Defined Benefit Plan, Fair Value of Plan Assets, Excluding Net Asset Value investments | 9 | 249 | |
Defined Benefit Plan, Alternative Investments, Fair Value Of Plan Assets | 1,896 | 2,258 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Hedge Funds | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 2,627 | 3,398 | |
Defined Benefit Plan, Fair Value of Plan Assets, Excluding Net Asset Value investments | 0 | 0 | |
Defined Benefit Plan, Alternative Investments, Fair Value Of Plan Assets | 2,627 | 3,398 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 1 | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 1 | Fixed Income Funds | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 1 | Common Collective Trust, Cash And Cash Equivalents | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 1 | Common Collective Trust - Equity | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 1 | Common Collective Trust - Fixed Income | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 1 | Common Collective Trust - Real Estate | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 1 | Hedge Funds | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 2 | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 50,141 | 54,228 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 2 | Fixed Income Funds | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 261 | 184 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 2 | Common Collective Trust, Cash And Cash Equivalents | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 1,388 | 314 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 2 | Common Collective Trust - Equity | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 9,436 | 15,749 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 2 | Common Collective Trust - Fixed Income | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 39,047 | 37,732 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 2 | Common Collective Trust - Real Estate | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 9 | 249 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 2 | Hedge Funds | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 3 | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 3 | Fixed Income Funds | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 3 | Common Collective Trust, Cash And Cash Equivalents | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 3 | Common Collective Trust - Equity | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 3 | Common Collective Trust - Fixed Income | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 3 | Common Collective Trust - Real Estate | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | 0 | 0 | |
Fair Value, Measurements, Recurring | Defined Benefit Pension Plan | Fair Value, Level 3 | Hedge Funds | |||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | |||
Total investments measured at fair value | $ 0 | $ 0 |
Employee Benefit Plans_ Changes
Employee Benefit Plans: Changes in Benefit Obligations (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Defined Benefit Pension Plan | |||
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] | |||
Projected benefit obligation at beginning of year | $ 67,562 | $ 64,973 | |
Service cost | 516 | 545 | $ 606 |
Interest cost | 2,194 | 2,341 | 2,499 |
Actuarial loss (gain) | (2,878) | 4,008 | |
Benefits paid | (3,562) | (3,445) | |
Plan participants transfer to affiliate | (1,913) | (860) | |
Plan participants’ contributions | 0 | 0 | |
Projected benefit obligation at end of year | 61,919 | 67,562 | 64,973 |
Supplemental Non-qualified Defined Benefit Retirement Plans | |||
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] | |||
Projected benefit obligation at beginning of year | 3,418 | 3,404 | |
Service cost | 0 | 0 | 0 |
Interest cost | 108 | 116 | 122 |
Actuarial loss (gain) | (296) | 144 | |
Benefits paid | (238) | (246) | |
Plan participants transfer to affiliate | 0 | 0 | |
Plan participants’ contributions | 0 | 0 | |
Projected benefit obligation at end of year | 2,992 | 3,418 | 3,404 |
Non-pension Defined Benefit Postretirement Healthcare Plan | |||
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] | |||
Projected benefit obligation at beginning of year | 5,970 | 5,843 | |
Service cost | 193 | 206 | 204 |
Interest cost | 179 | 176 | 187 |
Actuarial loss (gain) | (889) | 130 | |
Benefits paid | (389) | (348) | |
Plan participants transfer to affiliate | (129) | (137) | |
Plan participants’ contributions | 120 | 100 | |
Projected benefit obligation at end of year | $ 5,055 | $ 5,970 | $ 5,843 |
Employee Benefit Plans_ Chang_2
Employee Benefit Plans: Changes in Plan Assets (Details) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2018 | Dec. 31, 2017 | |
Defined Benefit Pension Plan | ||
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] | ||
Beginning market value of plan assets | $ 59,884 | $ 53,888 |
Investment income (loss) | (1,884) | 6,150 |
Employer contributions | 1,795 | 4,000 |
Retiree contributions | 0 | 0 |
Benefits paid | (3,563) | (3,445) |
Asset transfer to affiliate | (1,568) | (709) |
Ending fair value of plan assets | 54,664 | 59,884 |
Supplemental Non-qualified Defined Benefit Retirement Plans | ||
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] | ||
Beginning market value of plan assets | 0 | 0 |
Investment income (loss) | 0 | 0 |
Employer contributions | 238 | 246 |
Retiree contributions | 0 | 0 |
Defined Benefit Plan Benefits Paid From Plan and Company Assets | (238) | (246) |
Asset transfer to affiliate | 0 | 0 |
Ending fair value of plan assets | 0 | 0 |
Non-pension Defined Benefit Postretirement Healthcare Plan | ||
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] | ||
Beginning market value of plan assets | 0 | 0 |
Investment income (loss) | 0 | 0 |
Employer contributions | 268 | 248 |
Retiree contributions | 120 | 100 |
Benefits paid | (388) | (348) |
Asset transfer to affiliate | 0 | 0 |
Ending fair value of plan assets | $ 0 | $ 0 |
Employee Benefit Plans_ Amounts
Employee Benefit Plans: Amounts Recognized in the Balance Sheet (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017 |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Non-current liability | $ (14,606) | $ (16,285) |
Regulatory Liabilities | (163,216) | (148,855) |
Defined Benefit Pension Plan | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Regulatory asset | 19,099 | 18,998 |
Current liability | 0 | 0 |
Non-current liability | (7,255) | (7,676) |
Regulatory Liabilities | 0 | 0 |
Supplemental Non-qualified Defined Benefit Retirement Plans | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Regulatory asset | 0 | 0 |
Current liability | (230) | (245) |
Non-current liability | (2,762) | (3,173) |
Regulatory Liabilities | 0 | 0 |
Non-pension Defined Benefit Postretirement Healthcare Plan | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Regulatory asset | 0 | 0 |
Current liability | (466) | (534) |
Non-current liability | (4,589) | (5,436) |
Regulatory Liabilities | $ (2,441) | $ (1,758) |
Employee Benefit Plans_ Accumul
Employee Benefit Plans: Accumulated Benefit Obligation (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017 |
Defined Benefit Pension Plan | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Accumulated benefit obligation | $ 59,987 | $ 64,782 |
Supplemental Non-qualified Defined Benefit Retirement Plans | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Accumulated benefit obligation | 2,992 | 3,418 |
Non-pension Defined Benefit Postretirement Healthcare Plan | ||
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
Accumulated benefit obligation | $ 5,055 | $ 5,970 |
Employee Benefit Plans_ Compone
Employee Benefit Plans: Components of Net Periodic Expense (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Defined Benefit Pension Plan | |||
Defined Benefit Plan Disclosure [Line Items] | |||
Service cost | $ 516 | $ 545 | $ 606 |
Interest cost | 2,194 | 2,341 | 2,499 |
Expected return on assets | (3,545) | (3,591) | (3,632) |
Amortization of prior service cost (credits) | 43 | 43 | 43 |
Recognized net actuarial loss (gain) | 2,063 | 1,230 | 1,995 |
Net periodic expense | 1,271 | 568 | 1,511 |
Supplemental Non-qualified Defined Benefit Retirement Plans | |||
Defined Benefit Plan Disclosure [Line Items] | |||
Service cost | 0 | 0 | 0 |
Interest cost | 108 | 116 | 122 |
Expected return on assets | 0 | 0 | 0 |
Amortization of prior service cost (credits) | 0 | 0 | 0 |
Recognized net actuarial loss (gain) | 103 | 87 | 82 |
Net periodic expense | 211 | 203 | 204 |
Non-pension Defined Benefit Postretirement Healthcare Plan | |||
Defined Benefit Plan Disclosure [Line Items] | |||
Service cost | 193 | 206 | 204 |
Interest cost | 179 | 176 | 187 |
Expected return on assets | 0 | 0 | 0 |
Amortization of prior service cost (credits) | (336) | (336) | (337) |
Recognized net actuarial loss (gain) | 0 | 0 | 0 |
Net periodic expense | $ 36 | $ 46 | $ 54 |
Employee Benefit Plans_ Accum_2
Employee Benefit Plans: Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017 |
Defined Benefit Pension Plan | ||
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax [Abstract] | ||
Net (gain) loss | $ 0 | $ 0 |
Total AOCI | 0 | 0 |
Supplemental Non-qualified Defined Benefit Retirement Plans | ||
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax [Abstract] | ||
Net (gain) loss | 391 | 707 |
Total AOCI | 391 | 707 |
Non-pension Defined Benefit Postretirement Healthcare Plan | ||
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax [Abstract] | ||
Net (gain) loss | 0 | 0 |
Total AOCI | $ 0 | $ 0 |
Employee Benefit Plans_ Defined
Employee Benefit Plans: Defined Benefit Plans Assumptions (Details) | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Healthcare trend rate pre-65 | |||
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract] | |||
Trend for next year | 6.70% | 7.00% | |
Ultimate trend rate | 4.50% | 4.50% | |
Year Ultimate Trend Reached | 2,027 | 2,027 | |
Healthcare trend rate post-65 | |||
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract] | |||
Trend for next year | 4.94% | 5.00% | |
Ultimate trend rate | 4.50% | 4.50% | |
Year Ultimate Trend Reached | 2,026 | 2,026 | |
Defined Benefit Pension Plan | |||
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract] | |||
Discount rate | 4.40% | 3.71% | 4.27% |
Rate of increase in compensation levels | 3.52% | 3.43% | 3.47% |
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract] | |||
Discount rate | 3.71% | 4.27% | 4.63% |
Expected long-term rate of return on assets | 6.25% | 6.75% | 6.75% |
Rate of increase in compensation levels | 3.43% | 3.47% | 3.57% |
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract] | |||
Trend for next year | 4.40% | ||
Defined Benefit Plan Assumptions Used In Calculating Net Periodic Benefit Cost Expected Rate of Return On Assets For Next Fiscal Year | 6.00% | ||
Supplemental Non-qualified Defined Benefit Retirement Plans | |||
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract] | |||
Discount rate | 4.30% | 3.62% | 4.12% |
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract] | |||
Discount rate | 3.62% | 4.12% | 4.29% |
Non-pension Defined Benefit Postretirement Healthcare Plan | |||
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract] | |||
Discount rate | 4.28% | 3.60% | 3.84% |
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract] | |||
Discount rate | 3.60% | 3.84% | 4.03% |
Expected long-term rate of return on assets | 3.93% |
Employee Benefit Plans_ Project
Employee Benefit Plans: Projected Benefit Plan Payments (Details) $ in Thousands | Dec. 31, 2018USD ($) |
Defined Benefit Pension Plan | |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |
2,019 | $ 3,660 |
2,020 | 3,774 |
2,021 | 3,924 |
2,022 | 4,031 |
2,023 | 4,102 |
2024-2028 | 20,759 |
Supplemental Non-qualified Defined Benefit Retirement Plans | |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |
2,019 | 230 |
2,020 | 227 |
2,021 | 322 |
2,022 | 319 |
2,023 | 315 |
2024-2028 | 1,274 |
Non-pension Defined Benefit Postretirement Healthcare Plan | |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |
2,019 | 466 |
2,020 | 534 |
2,021 | 566 |
2,022 | 577 |
2,023 | 554 |
2024-2028 | $ 2,243 |
Related-Party Transactions_ Non
Related-Party Transactions: Non-Cash Dividend to Parent (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Parent | |||
Related Party Transaction [Line Items] | |||
Non-cash dividend to Parent | $ 36,000 | $ 42,000 | $ 52,500 |
Subsidiary of Common Parent | |||
Related Party Transaction [Line Items] | |||
Transfer from Investments | $ 36,000 | $ 42,000 | $ 52,500 |
Related-Party Transactions_ Rec
Related-Party Transactions: Receivables and Payables (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017 |
Related Party Transactions [Abstract] | ||
Accounts receivable from affiliates | $ 8,119 | $ 5,664 |
Accounts payable to affiliates | $ 25,804 | $ 25,653 |
Related-Party Transactions_ Mon
Related-Party Transactions: Money Pool Notes Receivable and Notes Payable (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Related Party Transaction [Line Items] | |||
Related Party Transaction, Rate | 3.06% | ||
Money pool notes payable | $ 38,690 | $ 13,397 | |
Parent | |||
Related Party Transaction [Line Items] | |||
Interest expense, related party | $ (1,300) | (1,400) | $ (1,900) |
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage | 1.00% | ||
Utility Money Pool | |||
Related Party Transaction [Line Items] | |||
Interest expense, related party | $ (401) | ||
Interest income, related party | $ 272 | $ 1,047 |
Related-Party Transactions_ Int
Related-Party Transactions: Interest Expense Allocation from Parent (Details) - USD ($) $ in Millions | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Parent | |||
Related Party Transaction [Line Items] | |||
Interest expense, related party | $ 1.3 | $ 1.4 | $ 1.9 |
Related-Party Transactions_ Oth
Related-Party Transactions: Other Balances and Transactions (Details) | 12 Months Ended |
Dec. 31, 2018Number_Of_Ground_Lease_ExtensionsMW | |
Wygen III Ground Lease with WRDC | |
Related Party Transaction [Line Items] | |
Lease Expiration Date | Dec. 31, 2050 |
Number of 20 Year Terms | Number_Of_Ground_Lease_Extensions | 3 |
Lessee, Operating Lease, Renewal Term | 20 years |
Happy Jack Wind Purchase Power Agreement | Subsidiary of Common Parent | |
Related Party Transaction [Line Items] | |
Long-term Contract for Purchase of Electric Power, Date of Contract Expiration | Sep. 3, 2028 |
Number of Megawatts Capacity Purchased | 15 |
Silver Sage Wind Power Purchase Agreement | |
Related Party Transaction [Line Items] | |
Long-term Contract for Purchase of Electric Power, Date of Contract Expiration | Sep. 30, 2029 |
Silver Sage Wind Power Purchase Agreement | Renewable Wind Energy, Wyoming Electric | |
Related Party Transaction [Line Items] | |
Number of Megawatts Capacity Purchased | 20 |
Related-Party Transactions_ Rel
Related-Party Transactions: Related-Party Gas Transportation Service Agreement (Details) | 12 Months Ended |
Dec. 31, 2018 | |
Purchase Of Natural Gas, Wyoming Gas | Subsidiary of Common Parent | |
Related Party Transaction [Line Items] | |
Long-term Purchase Commitment, Period | 40 years |
Related-Party Transactions_ R_2
Related-Party Transactions: Related-Party Revenue and Purchases (Details) - Subsidiary of Common Parent - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Horizon Point Shared Facility Revenues | |||
Related Party Transaction [Line Items] | |||
Revenue from Related Parties | $ 11,211 | $ 1,420 | $ 0 |
Energy sold to Wyoming Electric | |||
Related Party Transaction [Line Items] | |||
Revenue from Related Parties | 2,064 | 2,481 | 2,440 |
Lease Agreements | |||
Related Party Transaction [Line Items] | |||
Revenue from Related Parties | 3,634 | 3,680 | 5,046 |
Coal, Purchased | |||
Related Party Transaction [Line Items] | |||
Costs and Expenses, Related Party | 17,532 | 15,948 | 16,227 |
Purchase of Excess Energy, Wyoming Electric | |||
Related Party Transaction [Line Items] | |||
Costs and Expenses, Related Party | 511 | 601 | 252 |
Happy Jack Wind Purchase Power Agreement | |||
Related Party Transaction [Line Items] | |||
Costs and Expenses, Related Party | 1,942 | 1,924 | 1,918 |
Silver Sage Wind Power Purchase Agreement | |||
Related Party Transaction [Line Items] | |||
Costs and Expenses, Related Party | 3,586 | 3,290 | 3,300 |
Purchase Of Natural Gas, Cheyenne Light | |||
Related Party Transaction [Line Items] | |||
Costs and Expenses, Related Party | $ 364 | $ 393 | $ 399 |
Related-Party Transactions_ R_3
Related-Party Transactions: Related-Party Corporate Support (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Allocated Costs From Related Parties | Subsidiary of Common Parent | |||
Related Party Transaction [Line Items] | |||
Costs and Expenses, Related Party | $ 34,578 | $ 27,869 | $ 25,748 |
Supplemental Cash Flow Inform_3
Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] | |||
Property, plant and equipment acquired with accrued liabilities | $ 15,180 | $ 6,565 | $ 5,521 |
Interest and Income Taxes (Paid) Refunded, Cash Flow Information [Abstract] | |||
Interest (net of amounts capitalized) | (21,988) | (21,517) | (21,320) |
Income taxes (paid) refunded | (10,394) | (12,719) | 0 |
Subsidiary of Common Parent | |||
Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] | |||
Non-cash decrease to money pool note receivable, net | (36,000) | (42,000) | (52,500) |
Parent | |||
Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] | |||
Non-cash dividend to Parent | $ 36,000 | $ 42,000 | $ 52,500 |
Commitment and Contingencies (D
Commitment and Contingencies (Details) $ in Thousands | 12 Months Ended | ||
Dec. 31, 2018USD ($)MW | Dec. 31, 2017USD ($) | Dec. 31, 2016USD ($) | |
Contractual Obligation, Fiscal Year Maturity [Abstract] | |||
2,019 | $ 8,050 | ||
2,020 | 7,693 | ||
2,021 | 7,059 | ||
2,022 | 7,059 | ||
2,023 | 7,056 | ||
Thereafter | $ 21,947 | ||
Osage Plant Ash Impoundment | |||
Sales Capacity Commitments [Abstract] | |||
Commitment and Contingencies, Environmental Matters, Post Closure Monitoring, Period | 30 years | ||
Osage Plant, Industrial Rubble Landfill | |||
Sales Capacity Commitments [Abstract] | |||
Commitment and Contingencies, Environmental Matters, Post Closure Monitoring, Period | 30 years | ||
M D U, Montana Dakota Utilities | |||
Sales Capacity Commitments [Abstract] | |||
Long-term Contract To Sell Electric Power, Date of Contract Expiration | Dec. 31, 2023 | ||
M D U, Montana Dakota Utilities | Maximum | |||
Sales Capacity Commitments [Abstract] | |||
Number of MW Sold Under Long-Term Contract | MW | 50 | ||
City Of Gillette | |||
Sales Capacity Commitments [Abstract] | |||
Number of MW Sold Under Long-Term Contract | MW | 23 | ||
Long-term Contract To Sell Electric Power, Date of Contract Expiration | Sep. 3, 2019 | ||
Purchase Power Contract, MEAN, 10 M W | |||
Sales Capacity Commitments [Abstract] | |||
Long-term Contract To Sell Electric Power, Date of Contract Expiration | May 31, 2028 | ||
Macquarie Energy, LLC Supply Agreement | |||
Sales Capacity Commitments [Abstract] | |||
Number of MW Sold Under Long-Term Contract | MW | 50 | ||
Long-term Contract To Sell Electric Power, Date of Contract Expiration | Dec. 31, 2021 | ||
Wygen III Generating Facility | M D U, Montana Dakota Utilities | |||
Sales Capacity Commitments [Abstract] | |||
Number of MW Sold Under Long-Term Contract | MW | 25 | ||
Long-term Contract To Sell Electric Power, Date of Contract Expiration | Jan. 31, 2023 | ||
Wygen III Generating Facility | Purchase Power Contract, MEAN, 10 M W | |||
Sales Capacity Commitments [Abstract] | |||
Number of MW Sold Under Long-Term Contract | MW | 10 | ||
Neil Simpson II | Purchase Power Contract, MEAN, 10 M W | |||
Sales Capacity Commitments [Abstract] | |||
Number of MW Sold Under Long-Term Contract | MW | 10 | ||
Thunder Creek - Gas Transport Capacity | |||
Long-term Purchase Commitment [Line Items] | |||
Cost of Goods and Services Sold | $ 633 | $ 633 | $ 633 |
PacifiCorp Purchase Power Agreement | |||
Long-term Purchase Commitment [Line Items] | |||
Long-term Contract for Purchase of Electric Power, Date of Contract Expiration | Dec. 31, 2023 | ||
Number of Megawatts Capacity Purchased | MW | 50 | ||
Cost of Goods and Services Sold | $ 13,681 | 13,218 | 12,221 |
PacifiCorp Transmission | |||
Long-term Purchase Commitment [Line Items] | |||
Long-term Contract for Purchase of Electric Power, Date of Contract Expiration | Dec. 31, 2023 | ||
Number of Megawatts Capacity Purchased | MW | 50 | ||
Cost of Goods and Services Sold | $ 1,742 | 1,671 | 1,428 |
Platte River Power Authority Wind Power Agreement | |||
Long-term Purchase Commitment [Line Items] | |||
Long-term Contract for Purchase of Electric Power, Date of Contract Expiration | Sep. 30, 2029 | ||
Number of Megawatts Capacity Purchased | MW | 12 | ||
Cost of Goods and Services Sold | $ 223 | $ 0 | $ 0 |
Quarterly Financial information
Quarterly Financial information Data (Unaudited) (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended | |||||||||
Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Selected Quarterly Financial Information [Abstract] | |||||||||||
Revenue | $ 75,522 | $ 78,067 | $ 70,676 | $ 73,815 | $ 74,648 | $ 73,938 | $ 66,053 | $ 73,794 | $ 298,080 | $ 288,433 | $ 267,632 |
Operating income | 17,048 | 21,428 | 19,495 | 20,364 | 19,040 | 23,698 | 17,712 | 23,376 | 78,335 | 83,826 | 85,580 |
Net income | $ 9,443 | $ 13,317 | $ 11,125 | $ 11,760 | 15,615 | $ 13,826 | $ 9,287 | $ 12,570 | 45,645 | $ 51,298 | $ 45,138 |
Tax Cuts and Jobs Act of 2017, Change in Tax Rate, Income Tax Expense (Benefit) | $ (6,000) | $ 900 |