Black Hills (BKH) 10-Q 4 May 23 2023 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Mar. 31, 2023	Apr. 28, 2023
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Current Fiscal Year End Date	--12-31
Document Period End Date	Mar. 31, 2023
Document Transition Report	false
Entity File Number	001-31303
Entity Registrant Name	Black Hills Corporation
Entity Incorporation, State or Country Code	SD
Entity Tax Identification Number	46-0458824
Entity Address, Address Line One	7001 Mount Rushmore Road
Entity Address, City or Town	Rapid City
Entity Address, State or Province	SD
Entity Address, Postal Zip Code	57702
City Area Code	605
Local Phone Number	721-1700
Title of 12(b) Security	Common stock of $1.00 par value
Trading Symbol	BKH
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		66,660,004
Entity Central Index Key	0001130464
Amendment Flag	false
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q1

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Revenue:
Revenue	$ 921,159	$ 823,570
Operating expenses:
Fuel, purchased power and cost of natural gas sold	526,267	436,926
Operations and maintenance	140,988	136,132
Depreciation, depletion and amortization	61,643	60,463
Taxes - property and production	17,378	16,696
Total operating expenses	746,276	650,217
Operating income	174,883	173,353
Other income (expense):
Interest expense incurred net of amounts capitalized (including amortization of debt issuance costs, premiums and discounts)	(44,065)	(38,821)
Interest income	561	276
Other income, net	674	704
Total other income (expense)	(42,830)	(37,841)
Income before income taxes	132,053	135,512
Income tax (expense)	(14,673)	(14,488)
Net income	117,380	121,024
Net income attributable to non-controlling interest	(3,296)	(3,498)
Net income available for common stock	$ 114,084	$ 117,526
Earnings per share of common stock:
Earnings per share, Basic (usd per share)	$ 1.73	$ 1.82
Earnings per share, Diluted (usd per share)	$ 1.73	$ 1.82
Weighted average common shares outstanding:
Basic (in shares)	66,036	64,565
Diluted (in shares)	66,132	64,721

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Net income	$ 117,380	$ 121,024
Other comprehensive income (loss), net of tax:
Reclassification adjustments of benefit plan liability - prior service cost (net of tax of $0 and $6, respectively)	0	(18)
Reclassification adjustments of benefit plan liability - net loss (net of tax of $(16) and $(45), respectively)	28	143
Net unrealized gains (losses) on commodity derivatives (net of tax of $268 and $(340), respectively)	(855)	1,047
Other comprehensive income (loss), net of tax	1,220	6
Comprehensive income	118,600	121,030
Less: comprehensive income attributable to non-controlling interest	(3,296)	(3,498)
Comprehensive income available for common stock	115,304	117,532
Interest rate swaps
Other comprehensive income (loss), net of tax:
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, after Tax	563	536
Commodity derivatives
Other comprehensive income (loss), net of tax:
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, after Tax	$ 1,484	$ (1,702)

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
(Tax) benefit on reclassification adjustment of benefit plan liability - net loss	$ (16)	$ (45)
(Tax) benefit on reclassification adjustment of benefit plan liability - prior service cost	0	6
Interest Rate Swap
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification,Tax (Benefit)	(150)	(177)
Commodity Contract
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification,Tax (Benefit)	(466)	552
(Tax) benefit on net unrealized gains (losses) on commodity derivatives	$ 268	$ (340)

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 39,365	$ 21,430
Restricted cash and equivalents	5,765	5,555
Accounts receivable, net	477,089	508,192
Materials, supplies and fuel	129,960	207,421
Derivative assets, current	153	582
Income tax receivable, net	17,772	17,637
Regulatory assets, current	214,838	260,312
Other current assets	33,376	50,579
Total current assets	918,318	1,071,708
Property, plant and equipment	8,466,173	8,374,790
Less accumulated depreciation and depletion	(1,628,772)	(1,576,842)
Total property, plant and equipment, net	6,837,401	6,797,948
Other assets:
Goodwill	1,299,454	1,299,454
Intangible assets, net	9,296	9,589
Regulatory assets, non-current	347,031	392,669
Other assets, non-current	48,636	46,862
Total other assets, non-current	1,704,417	1,748,574
TOTAL ASSETS	9,460,136	9,618,230
Current liabilities:
Accounts payable	173,221	310,020
Accrued liabilities	228,861	243,457
Derivative liabilities, current	1,729	6,600
Regulatory liabilities, current	110,100	46,013
Notes payable	0	535,600
Current maturities of long-term debt	525,000	525,000
Total current liabilities	1,038,911	1,666,690
Long-term debt, net of current maturities	3,954,409	3,607,340
Deferred credits and other liabilities:
Deferred income tax liabilities, net	535,852	508,941
Regulatory liabilities, non-current	466,961	472,560
Benefit plan liabilities	117,765	116,742
Other deferred credits and other liabilities	154,507	156,062
Total deferred credits and other liabilities	1,275,085	1,254,305
Commitments, contingencies and guarantees (Note 3)
Equity:
Common stock $1 par value; 100,000,000 shares authorized; issued 66,670,709 and 66,140,396 shares, respectively	66,671	66,140
Additional paid-in capital	1,911,476	1,882,653
Retained earnings	1,136,844	1,064,122
Treasury stock, at cost - 41,114 and 36,726 shares, respectively	(2,697)	(2,435)
Accumulated other comprehensive income (loss)	(14,347)	(15,567)
Total stockholders’ equity	3,097,947	2,994,913
Non-controlling interest	93,784	94,982
Total equity	3,191,731	3,089,895
TOTAL LIABILITIES AND TOTAL EQUITY	$ 9,460,136	$ 9,618,230

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Common stock, par value (usd per share)	$ 1	$ 1
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares, issued	66,670,709	66,140,396
Treasury stock, shares	41,114	36,726

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Operating activities:
Net income	$ 117,380	$ 121,024
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion and amortization	61,643	60,463
Deferred financing cost amortization	2,410	2,475
Stock compensation	1,784	3,638
Deferred income taxes	14,858	14,462
Employee benefit plans	3,021	1,173
Other adjustments, net	(2,816)	5,337
Change in certain operating assets and liabilities:
Materials, supplies and fuel	76,122	34,995
Accounts receivable and other current assets	28,729	(71,241)
Accounts payable and other current liabilities	(127,233)	(8,422)
Regulatory assets	154,666	98,528
Other operating activities, net	(1,819)	1,689
Net cash provided by operating activities	328,745	264,121
Investing activities:
Property, plant and equipment additions	(119,105)	(136,779)
Other investing activities	17,600	(1,065)
Net cash (used in) investing activities	(101,505)	(137,844)
Financing activities:
Dividends paid on common stock	(41,362)	(38,533)
Common stock issued	27,383	3,791
Net borrowings (payments) of Revolving Credit Facility and CP Program	(535,600)	(78,700)
Long-term debt - issuance	350,000	0
Distributions to non-controlling interests	(4,494)	(4,420)
Other financing activities	(5,022)	(878)
Net cash (used in) financing activities	(209,095)	(118,740)
Net change in cash, restricted cash and cash equivalents	18,145	7,537
Cash, restricted cash and cash equivalents beginning of period	26,985	13,810
Cash, restricted cash and cash equivalents end of period	45,130	21,347
Supplemental cash flow information:
Interest (net of amounts capitalized)	(27,569)	(23,605)
Income taxes	49	0
Accrued property, plant and equipment purchases at March 31,	$ 42,102	$ 39,559

Consolidated Statements of Equi

Consolidated Statements of Equity - USD ($) $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest
Beginning balance (in shares) at Dec. 31, 2021		64,793,095	54,078
Beginning balance at Dec. 31, 2021	$ 2,887,123	$ 64,793	$ (3,509)	$ 1,783,436	$ 962,458	$ (20,084)	$ 100,029
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	121,024				117,526		3,498
Other comprehensive income, net of tax	6					6
Dividends on common stock	(38,533)				(38,533)
Share-based compensation (in shares)		425	(34,393)
Share-based compensation	2,031		$ 2,222	(191)
Issuance of common stock (in shares)		55,707
Issuance of common stock	3,832	$ 56		3,776
Issuance costs	(41)			(41)
Distributions to non-controlling interest	(4,420)						(4,420)
Ending balance (in shares) at Mar. 31, 2022		64,849,227	19,685
Ending balance at Mar. 31, 2022	2,971,022	$ 64,849	$ (1,287)	1,786,980	1,041,451	(20,078)	99,107
Beginning balance (in shares) at Dec. 31, 2022		66,140,396	36,726
Beginning balance at Dec. 31, 2022	3,089,895	$ 66,140	$ (2,435)	1,882,653	1,064,122	(15,567)	94,982
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	117,380				114,084		3,296
Other comprehensive income, net of tax	1,220					1,220
Dividends on common stock	(41,362)				(41,362)
Share-based compensation (in shares)		84,735	4,388
Share-based compensation	1,709	$ 85	$ (262)	1,886
Issuance of common stock (in shares)		445,578
Issuance of common stock	27,719	$ 446		27,273
Issuance costs	(336)			(336)
Distributions to non-controlling interest	(4,494)						(4,494)
Ending balance (in shares) at Mar. 31, 2023		66,670,709	41,114
Ending balance at Mar. 31, 2023	$ 3,191,731	$ 66,671	$ (2,697)	$ 1,911,476	$ 1,136,844	$ (14,347)	$ 93,784

Consolidated Statements of Eq_2

Consolidated Statements of Equity (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Statement of Stockholders' Equity [Abstract]
Dividends on common stock (usd per share)	$ 0.625	$ 0.595

Management's Statement

Management's Statement	3 Months Ended
	Mar. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Management's Statement	(1) Management’s Statement The unaudited Consolidated Financial Statements included herein have been prepared by Black Hills Corporation (together with our subsidiaries the “Company”, “us”, “we” or “our”), pursuant to the rules and regulations of the SEC. Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America have been condensed or omitted pursuant to such rules and regulations; however, we believe that the footnotes adequately disclose the information presented. These Consolidated Financial Statements should be read in conjunction with the consolidated financial statements and the notes included in our 2022 Annual Report on Form 10-K. Use of Estimates and Basis of Presentation The information furnished in the accompanying Consolidated Financial Statements reflects certain estimates required and all adjustments, including accruals, which are, in the opinion of management, necessary for a fair presentation of the March 31, 2023, December 31, 2022 and March 31, 2022 financial information. Certain lines of business in which we operate are highly seasonal, and our interim results of operations are not necessarily indicative of the results of operations to be expected for an entire year. Recently Issued Accounting Standards Facilitation of the Effects of Reference Rate Reform on Financial Reporting, ASU 2020-04 In March 2020, the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting, which was subsequently amended by ASU 2021-01 and ASU 2022-06. The standard provides relief for companies preparing for discontinuation of interest rates, such as LIBOR, and allows optional expedients and exceptions for applying GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. The amendments in this update are elective and are effective upon the ASU issuance through December 31, 2024. We are currently evaluating if we will apply the optional guidance as we assess the impact of the discontinuance of LIBOR on our current arrangements. We do not expect the ASU to have a material impact on our financial position, results of operations and cash flows.

Regulatory Matters

Regulatory Matters	3 Months Ended
	Mar. 31, 2023
Regulated Operations [Abstract]
Regulatory Matters	(2) Regulatory Matters We had the following regulatory assets and liabilities (in thousands): As of As of March 31, 2023 December 31, 2022 Regulatory assets Winter Storm Uri (a) $ 253,835 $ 347,980 Deferred energy and fuel cost adjustments (b) 79,020 72,580 Deferred gas cost adjustments (b) 16,047 12,147 Gas price derivatives (b) - 8,793 Deferred taxes on AFUDC (b) 7,482 7,333 Employee benefit plans and related deferred taxes (c) 88,710 89,259 Environmental (b) 1,341 1,343 Loss on reacquired debt (b) 18,764 19,213 Deferred taxes on flow through accounting (b) 74,022 69,529 Decommissioning costs (b) 2,850 3,472 Other regulatory assets (b) 19,798 21,332 Total regulatory assets 561,869 652,981 Less current regulatory assets ( 214,838 ) ( 260,312 ) Regulatory assets, non-current $ 347,031 $ 392,669 Regulatory liabilities Deferred energy and gas costs (b) $ 106,030 $ 41,722 Employee benefit plan costs and related deferred taxes (c) 33,839 34,258 Cost of removal (b) 177,453 175,614 Excess deferred income taxes (c) 248,126 254,833 Other regulatory liabilities (c) 11,613 12,146 Total regulatory liabilities 577,061 518,573 Less current regulatory liabilities ( 110,100 ) ( 46,013 ) Regulatory liabilities, non-current $ 466,961 $ 472,560 (a) Timing of Winter Storm Uri incremental cost recovery and associated carrying costs vary by jurisdiction. (b) Recovery or repayment of costs, but we are not 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 Activity Except as discussed below, there have been no other significant changes to our Regulatory Matters from those previously disclosed in Note 2 of the Notes to the Consolidated Financial Statements in our 2022 Annual Report on Form 10-K. RMNG On April 7, 2023, RMNG filed a settlement agreement with the CPUC for its rate review filed on October 7, 2022. The agreement is expected to generate $ 8.2 million in new annual revenue and establishes a weighted average cost of capital of 6.93 % with a capital structure that reflects an equity range of 50 % to 52 %, a debt range of 50 % to 48 % and a return on equity range of 9.5 % to 9.7 %. The settlement also shifts $ 8.3 million of SSIR revenues to base rates and terminates the SSIR. The agreement is awaiting a decision by an administrative law judge, with new rates expected in the third quarter of 2023. Wyoming Electric On June 1, 2022, Wyoming Electric filed a rate review with the WPSC seeking recovery of significant infrastructure investments in its 1330 -mile electric distribution and 59 -mile electric transmission systems. On January 26, 2023, the WPSC approved a settlement agreement with intervening parties for a general rate increase. The settlement is expected to generate $ 8.7 million in new annual revenue with a capital structure of 52 % equity and 48 % debt and a return on equity of 9.75 %. New rates were effective March 1, 2023. The agreement also includes approval of a new rider that will be filed annually to recover transmission investment and expenses.

Commitment, Contingencies And G

Commitment, Contingencies And Guarantees	3 Months Ended
	Mar. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments, Contingencies and Guarantees	(3) Commitments, Contingencies and Guarantees There have been no significant changes to commitments, contingencies and guarantees from those previously disclosed in Note 3 of our Notes to the Consolidated Financial Statements in our 2022 Annual Report on Form 10-K.

Revenue

Revenue	3 Months Ended
	Mar. 31, 2023
Revenue from Contract with Customer [Abstract]
Revenue	(4) Revenue The following tables depict the disaggregation of revenue, including intercompany revenue, from contracts with customers by customer type and timing of revenue recognition for each of the reportable segments for the three months ended March 31, 2023 and 2022. Sales tax and other similar taxes are excluded from revenues. Three Months Ended March 31, 2023 Electric Utilities Gas Utilities Inter-company Revenues Total Customer types: (in thousands) Retail $ 174,903 $ 635,545 $ - $ 810,448 Transportation - 52,843 ( 115 ) 52,728 Wholesale 9,398 - - 9,398 Market - off-system sales 16,124 281 - 16,405 Transmission/Other 17,404 10,023 ( 4,351 ) 23,076 Revenue from contracts with customers $ 217,829 $ 698,692 $ ( 4,466 ) $ 912,055 Other revenues 880 8,224 - 9,104 Total revenues $ 218,709 $ 706,916 $ ( 4,466 ) $ 921,159 Timing of revenue recognition: Services transferred at a point in time $ 8,657 $ - $ - $ 8,657 Services transferred over time 209,172 698,692 ( 4,466 ) 903,398 Revenue from contracts with customers $ 217,829 $ 698,692 $ ( 4,466 ) $ 912,055 Three Months Ended March 31, 2022 Electric Utilities Gas Utilities Inter-company Revenues Total Customer types: (in thousands) Retail $ 172,806 $ 561,013 $ - $ 733,819 Transportation - 49,523 ( 99 ) 49,424 Wholesale 10,275 - - 10,275 Market - off-system sales 7,154 238 - 7,392 Transmission/Other 15,433 9,575 ( 4,149 ) 20,859 Revenue from contracts with customers $ 205,668 $ 620,349 $ ( 4,248 ) $ 821,769 Other revenues 870 1,043 ( 112 ) 1,801 Total revenues $ 206,538 $ 621,392 $ ( 4,360 ) $ 823,570 Timing of revenue recognition: Services transferred at a point in time $ 7,113 $ - $ - $ 7,113 Services transferred over time 198,555 620,349 ( 4,248 ) 814,656 Revenue from contracts with customers $ 205,668 $ 620,349 $ ( 4,248 ) $ 821,769

Financing

Financing	3 Months Ended
	Mar. 31, 2023
Debt Disclosure [Abstract]
Financing	(5) Financing Short-term Debt Revolving Credit Facility and CP Program Our Revolving Credit Facility and CP Program, which are classified as Notes payable on the Consolidated Balance Sheets, had the following borrowings, outstanding letters of credit, and available capacity (dollars in thousands): March 31, 2023 December 31, 2022 Amount outstanding $ — $ 535,600 Letters of credit (a) $ 2,401 $ 24,626 Available capacity $ 747,599 $ 189,774 Weighted average interest rates N/A 4.88 % (a) Letters of credit are off-balance sheet commitments that reduce the borrowing capacity available on our corporate Revolving Credit Facility . Revolving Credit Facility and CP Program borrowing activity was as follows (dollars in thousands): Three Months Ended March 31, 2023 2022 Maximum amount outstanding (based on daily outstanding balances) $ 548,700 $ 429,000 Average amount outstanding (based on daily outstanding balances) $ 331,268 $ 360,823 Weighted average interest rates 4.91 % 0.44 % Long-term Debt On March 7, 2023, we completed a public debt offering of $ 350 million, 5.95 % five year senior unsecured notes due March 15, 2028. The proceeds from the offering, which were net of $ 4.2 million of deferred financing costs, were used to repay notes outstanding under our CP Program and for other general corporate purposes. Debt Covenants Revolving Credit Facility Under our Revolving Credit Facility, we are required to maintain a Consolidated Indebtedness to Capitalization Ratio not to exceed 0.65 to 1.00. Subject to applicable cure periods, a violation of any of these covenants would constitute an event of default that entitles the lenders to terminate their remaining commitments and accelerate all principal and interest outstanding. We were in compliance with our covenants at March 31, 2023, as shown below: As of March 31, 2023 Covenant Requirement Consolidated Indebtedness to Capitalization Ratio 59.1 % Less than 65 % Wyoming Electric Covenants within Wyoming Electric's financing agreements require Wyoming Electric to maintain a debt to capitalization ratio of no more than 0.60 to 1.00. As of March 31, 2023, we were in compliance with these financial covenants. Equity At-the-Market Equity Offering Program ATM activity was as follows (net proceeds and issuance costs in millions): Three Months Ended March 31, 2023 2022 Proceeds, (net of issuance costs of $( 0.3 ), $( 0.0 ) respectively) $ 27.4 $ 3.8 Average price per share $ 62.21 $ 68.79 Number of shares issued 445,578 55,707 As of March 31, 2023 , there were 34,040 shares issued, but not settled.

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2023
Earnings Per Share [Abstract]
Earnings Per Share	(6) Earnings Per Share A reconciliation of share amounts used to compute earnings per share in the accompanying Consolidated Statements of Income was as follows (in thousands, except per share amounts): Three Months Ended March 31, 2023 2022 Net income available for common stock $ 114,084 $ 117,526 Weighted average shares - basic 66,036 64,565 Dilutive effect of: Equity compensation 96 156 Weighted average shares - diluted 66,132 64,721 Earnings per share of common stock: Earnings per share, Basic $ 1.73 $ 1.82 Earnings per share, Diluted $ 1.73 $ 1.82 The following securities were excluded from the diluted earnings per share computation because of their anti-dilutive nature (in thousands): Three Months Ended March 31, 2023 2022 Equity compensation 53 - Anti-dilutive shares 53 -

Risk Management And Derivatives

Risk Management And Derivatives	3 Months Ended
	Mar. 31, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Risk Management And Derivatives	(7) Risk Management and Derivatives Market and Credit Risk Disclosures Our activities in the energy industry expose us to a number of risks in the normal operations of our businesses. Depending on the activity, we are exposed to varying degrees of market risk and credit risk. Valuation methodologies for our derivatives are detailed within Note 1 of the Notes to the Consolidated Financial Statements in our 2022 Annual Report on Form 10-K. Market Risk Market risk is the potential loss that may occur as a result of an adverse change in market price, rate or supply. We are exposed but not limited to, the following market risks: • Commodity price risk associated with our retail natural gas and wholesale electric power marketing activities and our fuel procurement for several of our gas-fired generation assets, which include market fluctuations due to unpredictable factors such as weather, geopolitical events, pandemics, market speculation, recession, inflation, pipeline constraints, and other factors that may impact natural gas and electric supply and demand; and • Interest rate risk associated with future debt, including reduced access to liquidity during periods of extreme capital markets volatility. Credit Risk Credit risk is the risk of financial loss resulting from non-performance of contractual obligations by a counterparty. We attempt to mitigate our credit exposure by conducting business primarily with high credit quality entities, setting tenor and credit limits commensurate with counterparty financial strength, obtaining master netting agreements and mitigating credit exposure with less creditworthy counterparties through parental guarantees, cash collateral requirements, letters of credit and other security agreements. We perform ongoing credit evaluations of our customers and adjust credit limits based upon payment history and the customers’ current creditworthiness, as determined by review of their current credit information. We maintain a provision for estimated credit losses based upon historical experience, changes in current market conditions, expected losses and any specific customer collection issue that is identified. Derivatives and Hedging Activity Our derivative and hedging activities included in the accompanying Consolidated Balance Sheets, Consolidated Statements of Income and Consolidated Statements of Comprehensive Income are detailed below and in Note 8 . The operations of our Utilities, including natural gas sold by our Gas Utilities and natural gas used by our Electric Utilities’ generation plants or those plants under PPAs where our Electric Utilities must provide the generation fuel (tolling agreements), expose our utility customers to natural gas price volatility. Therefore, as allowed or required by state utility commissions, we enter into commission approved hedging programs utilizing natural gas futures, options, over-the-counter swaps and basis swaps to reduce our customers’ underlying exposure to these fluctuations. These transactions are considered derivatives, and in accordance with accounting standards for derivatives and hedging, mark-to-market adjustments are recorded as Derivative assets or Derivative liabilities on the accompanying Consolidated Balance Sheets, net of balance sheet offsetting as permitted by GAAP. For our regulated Utilities’ hedging plans, unrealized and realized gains and losses, as well as option premiums and commissions on these transactions, are recorded as Regulatory assets or Regulatory liabilities in the accompanying Consolidated Balance Sheets in accordance with the state regulatory commission guidelines. When the related costs are recovered through our rates, the hedging activity is recognized in the Consolidated Statements of Income. We use wholesale power purchase and sale contracts to manage purchased power costs and load requirements associated with serving our electric customers. Periodically, certain wholesale energy contracts are considered derivative instruments due to not qualifying for the normal purchase and normal sales exception to derivative accounting. Changes in the fair value of these commodity derivatives are recognized in the Consolidated Statements of Income. To support our Choice Gas Program customers, we buy, sell and deliver natural gas at competitive prices by managing commodity price risk. As a result of these activities, this area of our business is exposed to risks associated with changes in the market price of natural gas. We manage our exposure to such risks using over-the-counter and exchange traded options and swaps with counterparties in anticipation of forecasted purchases and sales during time frames ranging from April 2023 through October 2025. A portion of our over-the-counter swaps have been designated as cash flow hedges to mitigate the commodity price risk associated with deliveries under fixed price forward contracts to deliver gas to our Choice Gas Program customers. The gain or loss on these designated derivatives is reported in AOCI in the accompanying Consolidated Balance Sheets and reclassified into earnings in the same period that the underlying hedged item is recognized in earnings. Effectiveness of our hedging position is evaluated at least quarterly. The contract or notional amounts and terms of the electric and natural gas derivative commodity instruments held at our Utilities are composed of both long and short positions. We had the following net long positions as of: March 31, 2023 December 31, 2022 Notional Amounts (MMBtus) Maximum Term (months) (a) Notional Amounts (MMBtus) Maximum Term (months) (a) Natural gas futures purchased - N/A 630,000 3 Natural gas options purchased, net - N/A 1,790,000 3 Natural gas basis swaps purchased - N/A 900,000 3 Natural gas over-the-counter swaps, net (b) 3,270,000 26 4,460,000 24 Natural gas physical contracts, net (c) 3,881,190 12 17,864,412 12 (a) Term reflects the maximum forward period hedged. (b) As of March 31, 2023 , 574,800 MMBtus of natural gas over-the-counter swaps purchases were designated as cash flow hedges. (c) Volumes exclude derivative contracts that qualify for the normal purchases and normal sales exception permitted by GAAP. We have certain derivative contracts which contain credit provisions. These credit provisions may require the Company to post collateral when credit exposure to the Company is in excess of a negotiated line of unsecured credit. At March 31, 2023, the Company poste d $ 0.6 million re lated to such provisions, which is included in Other current assets on the Consolidated Balance Sheets. Derivatives by Balance Sheet Classification As required by accounting standards for derivatives and hedges, fair values within the following tables are presented on a gross basis aside from the netting of asset and liability positions. Netting of positions is permitted in accordance with accounting standards for offsetting and under terms of our master netting agreements that allow us to settle positive and negative positions. The following table presents the fair value and balance sheet classification of our derivative instruments (in thousands) as of: Balance Sheet Location March 31, December 31, Derivatives designated as hedges: Asset derivative instruments: Current commodity derivatives Derivative assets, current $ - $ 118 Noncurrent commodity derivatives Other assets, non-current - 198 Liability derivative instruments: Current commodity derivatives Derivative liabilities, current ( 543 ) ( 1,703 ) Noncurrent commodity derivatives Other assets, non-current ( 2 ) - Total derivatives designated as hedges $ ( 545 ) $ ( 1,387 ) Derivatives not designated as hedges: Asset derivative instruments: Current commodity derivatives Derivative assets, current $ 153 $ 464 Noncurrent commodity derivatives Other assets, non-current 111 337 Liability derivative instruments: Current commodity derivatives Derivative liabilities, current ( 1,186 ) ( 4,897 ) Noncurrent commodity derivatives Other deferred credits and other liabilities ( 20 ) ( 18 ) Total derivatives not designated as hedges $ ( 942 ) $ ( 4,114 ) Derivatives Designated as Hedge Instruments The impacts of cash flow hedges on our Consolidated Statements of Comprehensive Income and Consolidated Statements of Income are presented below for the three months ended March 31, 2023 and 2022. Note that this presentation does not reflect the gains or losses arising from the underlying physical transactions; therefore, it is not indicative of the economic profit or loss we realized when the underlying physical and financial transactions were settled. Three Months Ended Three Months Ended 2023 2022 2023 2022 Derivatives in Cash Flow Hedging Relationships Amount of Gain/(Loss) Recognized in OCI Location on the Consolidated Statements of Income Amount of Gain/(Loss) Reclassified from AOCI into Income (in thousands) (in thousands) Interest rate swaps $ 713 $ 713 Interest expense $ ( 713 ) $ ( 713 ) Commodity derivatives 827 ( 867 ) Fuel, purchased power and cost of natural gas sold ( 1,950 ) 2,254 Total $ 1,540 $ ( 154 ) $ ( 2,663 ) $ 1,541 As of March 31, 2023, $ 3.6 million of net losses related to our interest rate swaps and commodity derivatives are expected to be reclassified from AOCI into earnings within the next 12 months. As market prices fluctuate, estimated and actual realized gains or losses will change during future periods. Derivatives Not Designated as Hedge Instruments The following table summarizes the impacts of derivative instruments not designated as hedge instruments on our Consolidated Statements of Income for the three months ended March 31, 2023 and 2022. Note that this presentation does not reflect the expected gains or losses arising from the underlying physical transactions; therefore, it is not indicative of the economic profit or loss we realized when the underlying physical and financial transactions were settled. Three Months Ended March 31, 2023 2022 Derivatives Not Designated as Hedging Instruments Location of Gain/(Loss) on Derivatives Recognized in Income Amount of Gain/(Loss) on Derivatives Recognized in Income Commodity derivatives - Natural Gas Fuel, purchased power and cost of natural gas sold $ ( 3,094 ) $ 3,494 $ ( 3,094 ) $ 3,494 As discussed above, financial instruments used in our regulated Gas Utilities are not designated as cash flow hedges. However, there is no earnings impact because the unrealized gains and losses arising from the use of these financial instruments are recorded as Regulatory assets or Regulatory liabilities. The net unrealized gains included in our Regulatory liability accounts related to these financial instruments in our Gas Utilities were $ 0.1 million as of March 31, 2023. The net unrealized losses included in our Regulatory asset accounts related to these financial instruments were $ 8.8 million as of December 31, 2022 . For our Electric Utilities, the unrealized gains and losses arising from these derivatives are recognized in the Consolidated Statements of Income.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurements	(8) Fair Value Measurements We use the following fair value hierarchy for determining inputs for our financial instruments. Our 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 about the 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 when the time between the valuation date and the delivery date of a transaction becomes shorter, positively impacting the availability of observable pricing inputs. Recurring Fair Value Measurements Derivatives The commodity contracts for our Utilities segments are valued using the market approach and include forward strip pricing at liquid delivery points, exchange-traded futures, options, basis swaps and over-the-counter swaps and options (Level 2) for wholesale electric energy and natural gas contracts. For exchange-traded futures, options and basis swap assets and liabilities, fair value was derived using broker quotes validated by the exchange settlement pricing for the applicable contract. For over-the-counter instruments, the fair value is obtained by utilizing a nationally recognized service that obtains observable inputs to compute the fair value, which we validate by comparing our valuation with the counterparty. The fair value of these swaps includes a credit valuation adjustment based on the credit spreads of the counterparties when we are in an unrealized gain position or on our own credit spread when we are in an unrealized loss position. For additional information, see Note 1 of our Notes to the Consolidated Financial Statements in our 2022 Annual Report on Form 10-K. The following tables set forth, by level within the fair value hierarchy, our gross assets and gross liabilities and related offsetting of cash collateral and contractual netting rights as permitted by GAAP that were accounted for at fair value on a recurring basis for derivative instruments. As of March 31, 2023 Level 1 Level 2 Level 3 Cash Collateral and Counterparty Netting (a) Total (in thousands) Assets: Commodity derivatives - Gas Utilities $ - $ 264 $ - $ - $ 264 Total $ - $ 264 $ - $ - $ 264 Liabilities: Commodity derivatives - Gas Utilities $ - $ 1,751 $ - $ - $ 1,751 Total $ - $ 1,751 $ - $ - $ 1,751 (a) As of March 31, 2023, we had no commodity derivative assets or liabilities, or related gross collateral amounts, that were subject to master netting agreements. As of December 31, 2022 Level 1 Level 2 Level 3 Cash Collateral and Counterparty Netting (a) Total (in thousands) Assets: Commodity derivatives - Gas Utilities $ - $ 5,407 $ - $ ( 4,290 ) $ 1,117 Total $ - $ 5,407 $ - $ ( 4,290 ) $ 1,117 Liabilities: Commodity derivatives - Gas Utilities $ - $ 11,455 $ - $ ( 4,837 ) $ 6,618 Total $ - $ 11,455 $ - $ ( 4,837 ) $ 6,618 (a) As of December 31, 2022 , $ 4.3 million of our commodity derivative assets and $ 4.8 million of our commodity derivative liabilities, as well as related gross collateral amounts, were subject to master netting agreements. Pension and Postretirement Plan Assets Fair value measurements also apply to the valuation of our pension and postretirement plan assets. Current accounting guidance requires employers to annually disclose information about the fair value measurements of their assets of a defined benefit pension or other postretirement plan. The fair value of these assets is presented in Note 13 to the Consolidated Financial Statements included in our 2022 Annual Report on Form 10-K. Other Fair Value Measures The carrying amount of cash and cash equivalents, restricted cash and equivalents and short-term borrowings approximates fair value due to their liquid or short-term nature. Cash, cash equivalents and restricted cash are classified in Level 1 in the fair value hierarchy. Notes payable consist of commercial paper borrowings and are not traded on an exchange; therefore, they are classified as Level 2 in the fair value hierarchy. The following table presents the carrying amounts and fair values of financial instruments not recorded at fair value on the Consolidated Balance Sheets (in thousands) as of: March 31, 2023 December 31, 2022 Carrying Amount Fair Value Carrying Amount Fair Value Long-term debt, including current maturities (a) $ 4,479,409 $ 4,205,369 $ 4,132,340 $ 3,760,848 (a) 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. Carrying amount of long-term debt is net of deferred financing costs.

Other Comprehensive Income

Other Comprehensive Income	3 Months Ended
	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Other Comprehensive Income	(9) Other Comprehensive Income We record deferred gains (losses) in AOCI related to interest rate swaps designated as cash flow hedges, commodity contracts designated as cash flow hedges and the amortization of components of our defined benefit plans. Deferred gains (losses) for our commodity contracts designated as cash flow hedges are recognized in earnings upon settlement, while deferred gains (losses) related to our interest rate swaps are recognized in earnings as they are amortized. The following table details reclassifications out of AOCI and into Net income. The amounts in parentheses below indicate decreases to Net income in the Consolidated Statements of Income for the period, net of tax (in thousands): Amount Reclassified from AOCI Location on the Consolidated Statements of Income Three Months Ended March 31, 2023 2022 Gains and (losses) on cash flow hedges: Interest rate swaps Interest expense $ ( 713 ) $ ( 713 ) Commodity contracts Fuel, purchased power and cost of natural gas sold ( 1,950 ) 2,254 $ ( 2,663 ) $ 1,541 Income tax Income tax expense 616 ( 375 ) Total reclassification adjustments related to cash flow hedges, net of tax $ ( 2,047 ) $ 1,166 Amortization of components of defined benefit plans: Prior service cost Operations and maintenance $ - $ 24 Actuarial gain (loss) Operations and maintenance ( 44 ) ( 188 ) $ ( 44 ) $ ( 164 ) Income tax Income tax expense 16 39 Total reclassification adjustments related to defined benefit plans, net of tax $ ( 28 ) $ ( 125 ) Total reclassifications $ ( 2,075 ) $ 1,041 Balances by classification included within AOCI, net of tax on the accompanying Consolidated Balance Sheets were as follows (in thousands): Derivatives Designated as Cash Flow Hedges Interest Rate Swaps Commodity Derivatives Employee Benefit Plans Total As of December 31, 2022 $ ( 8,255 ) $ ( 1,200 ) $ ( 6,112 ) $ ( 15,567 ) Other comprehensive income (loss) before reclassifications - ( 855 ) - ( 855 ) Amounts reclassified from AOCI 563 1,484 28 2,075 As of March 31, 2023 $ ( 7,692 ) $ ( 571 ) $ ( 6,084 ) $ ( 14,347 ) Derivatives Designated as Cash Flow Hedges Interest Rate Swaps Commodity Derivatives Employee Benefit Plans Total As of December 31, 2021 $ ( 10,384 ) $ 1,476 $ ( 11,176 ) $ ( 20,084 ) Other comprehensive income (loss) before reclassifications - 1,047 - 1,047 Amounts reclassified from AOCI 536 ( 1,702 ) 125 ( 1,041 ) As of March 31, 2022 $ ( 9,848 ) $ 821 $ ( 11,051 ) $ ( 20,078 )

Employee Benefits Plans

Employee Benefits Plans	3 Months Ended
	Mar. 31, 2023
Retirement Benefits [Abstract]
Employee Benefit Plans	(10) Employee Benefit Plans Components of Net Periodic Expense The components of net periodic expense were as follows (in thousands): Defined Benefit Pension Plan Supplemental Non-qualified Defined Benefit Plans Non-pension Defined Benefit Postretirement Healthcare Plan Three Months Ended March 31, 2023 2022 2023 2022 2023 2022 Service cost $ 614 $ 982 $ 914 $ ( 392 ) $ 381 $ 492 Interest cost 4,381 2,705 369 208 594 321 Expected return on plan assets ( 4,672 ) ( 4,631 ) - - ( 56 ) ( 31 ) Net amortization of prior service costs ( 17 ) ( 17 ) - - 10 ( 72 ) Recognized net actuarial loss (gain) 498 1,523 8 69 ( 3 ) 16 Net periodic expense (benefit) $ 804 $ 562 $ 1,291 $ ( 115 ) $ 926 $ 726 Plan Contributions Contributions to the Defined Benefit Pension Plan are cash contributions made directly to the Pension Plan Trust account. Contributions to the Postretirement Healthcare and Supplemental Plans are made in the form of benefit payments. Contributions made in the first three months of 2023 and anticipated contributions for 2023 and 2024 are as follows (in thousands): Contributions Made Additional Contributions Contributions Three Months Ended March 31, 2023 Anticipated for 2023 Anticipated for 2024 Defined Benefit Pension Plan $ - $ - $ - Non-pension Defined Benefit Postretirement Healthcare Plan $ 1,230 $ 3,690 $ 4,556 Supplemental Non-qualified Defined Benefit and Defined Contribution Plans $ 558 $ 1,673 $ 2,410

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2023
Income Tax Disclosure [Abstract]
Income Taxes	(11) Income Taxes IRS Revenue Procedure 2023-15 On April 14, 2023, the IRS released Revenue Procedure 2023-15 “Amounts paid to improve tangible property.” The Revenue Procedure provides a safe harbor method of accounting that taxpayers may use to determine whether expenses to repair, maintain, replace, or improve natural gas transmission and distribution property must be capitalized. We are currently assessing the Revenue Procedure to determine its impact on our tax repairs deduction. Income Tax Expense and Effective Tax Rates Three Months Ended March 31, 2023 Compared to the Three Months Ended March 31, 2022 Income tax expense for the three months ended March 31, 2023 was $ 14.7 million compared to $ 14.5 million reported for the same period in 2022. For the three months ended March 31, 2023, the effective tax rate was 11.1 % which was comparable to 10.7 % for the same period in 2022.

Business Segment Information

Business Segment Information	3 Months Ended
	Mar. 31, 2023
Segment Reporting Information, Additional Information [Abstract]
Business Segment Information	(12) Business Segment Information Segment information was as follows (in thousands): Total assets (net of intercompany eliminations) as of: March 31, 2023 December 31, 2022 Electric Utilities $ 3,922,496 $ 3,929,721 Gas Utilities 5,419,216 5,578,282 Corporate and Other 118,424 110,227 Total assets $ 9,460,136 $ 9,618,230 External Operating Revenue Inter-company Operating Revenue Three Months Ended March 31, 2023 Contract Customers Other Revenues Contract Customers Other Revenues Total Revenues Segment: Electric Utilities $ 215,012 $ 881 $ 2,816 $ - $ 218,709 Gas Utilities 697,043 8,223 1,650 - 706,916 Inter-company eliminations - - ( 4,466 ) - ( 4,466 ) Total $ 912,055 $ 9,104 $ - $ - $ 921,159 External Operating Revenue Inter-company Operating Revenue Three Months Ended March 31, 2022 Contract Customers Other Revenues Contract Customers Other Revenues Total Revenues Segment: Electric Utilities $ 202,739 $ 870 $ 2,929 $ - $ 206,538 Gas Utilities 619,030 931 1,319 112 621,392 Inter-company eliminations - - ( 4,248 ) ( 112 ) ( 4,360 ) Total $ 821,769 $ 1,801 $ - $ - $ 823,570 Three Months Ended March 31, 2023 2022 Operating income (loss): Electric Utilities $ 61,060 $ 50,746 Gas Utilities 114,625 123,540 Corporate and Other ( 802 ) ( 933 ) Operating income 174,883 173,353 Interest expense, net ( 43,504 ) ( 38,545 ) Other income, net 674 704 Income tax expense ( 14,673 ) ( 14,488 ) Net income 117,380 121,024 Net income attributable to non-controlling interest ( 3,296 ) ( 3,498 ) Net income available for common stock $ 114,084 $ 117,526

Selected Balance Sheet Informat

Selected Balance Sheet Information	3 Months Ended
	Mar. 31, 2023
Selected Balance Sheet Information [Abstract]
Selected Balance Sheet Information	(13) Selected Balance Sheet Information Accounts Receivable and Allowance for Credit Losses Following is a summary of Accounts receivable, net included in the accompanying Consolidated Balance Sheets (in thousands) as of: March 31, 2023 December 31, 2022 Billed Accounts Receivable $ 327,949 $ 267,571 Unbilled Revenue 154,571 243,574 Less: Allowance for Credit Losses ( 5,431 ) ( 2,953 ) Account Receivable, net $ 477,089 $ 508,192 Changes to allowance for credit losses for the three months ended March 31, 2023 and 2022, respectively, were as follows (in thousands): Balance at Beginning of Year Additions Charged to Costs and Expenses Recoveries and Other Additions Write-offs and Other Deductions Balance at March 31, 2023 $ 2,953 $ 3,703 $ 641 $ ( 1,866 ) $ 5,431 2022 $ 2,113 $ 3,416 $ 655 $ ( 1,698 ) $ 4,486 Materials, Supplies and Fuel The following amounts by major classification are included in Materials, supplies and fuel on the accompanying Consolidated Balance Sheets (in thousands) as of: March 31, 2023 December 31, 2022 Materials and supplies $ 102,328 $ 99,734 Fuel - Electric Utilities 6,808 3,115 Natural gas in storage 20,824 104,572 Total materials, supplies and fuel $ 129,960 $ 207,421 Accrued Liabilities The following amounts by major classification are included in Accrued liabilities on the accompanying Consolidated Balance Sheets (in thousands) as of: March 31, 2023 December 31, 2022 Accrued employee compensation, benefits and withholdings $ 48,555 $ 62,890 Accrued property taxes 54,694 52,430 Customer deposits and prepayments 42,124 47,655 Accrued interest 47,928 33,798 Other (none of which is individually significant) 35,560 46,684 Total accrued liabilities $ 228,861 $ 243,457

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2023
Subsequent Events [Abstract]
Subsequent Events	(14) Subsequent Events Except as described in Notes 2 and 11 , there have been no events subsequent to March 31, 2023, which would require recognition in the consolidated financial statements or disclosures.

Management's Statement (Policie

Management's Statement (Policies)	3 Months Ended
	Mar. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Use of Estimates and Basis of Presentation	Use of Estimates and Basis of Presentation The information furnished in the accompanying Consolidated Financial Statements reflects certain estimates required and all adjustments, including accruals, which are, in the opinion of management, necessary for a fair presentation of the March 31, 2023, December 31, 2022 and March 31, 2022 financial information. Certain lines of business in which we operate are highly seasonal, and our interim results of operations are not necessarily indicative of the results of operations to be expected for an entire year.
Recently Issued and Adopted Accounting Standards	Recently Issued Accounting Standards Facilitation of the Effects of Reference Rate Reform on Financial Reporting, ASU 2020-04 In March 2020, the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting, which was subsequently amended by ASU 2021-01 and ASU 2022-06. The standard provides relief for companies preparing for discontinuation of interest rates, such as LIBOR, and allows optional expedients and exceptions for applying GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. The amendments in this update are elective and are effective upon the ASU issuance through December 31, 2024. We are currently evaluating if we will apply the optional guidance as we assess the impact of the discontinuance of LIBOR on our current arrangements. We do not expect the ASU to have a material impact on our financial position, results of operations and cash flows.

Business Description And Signif

Business Description And Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accounts Receivable and Allowance for Doubtful Accounts	Following is a summary of Accounts receivable, net included in the accompanying Consolidated Balance Sheets (in thousands) as of: March 31, 2023 December 31, 2022 Billed Accounts Receivable $ 327,949 $ 267,571 Unbilled Revenue 154,571 243,574 Less: Allowance for Credit Losses ( 5,431 ) ( 2,953 ) Account Receivable, net $ 477,089 $ 508,192
Financing Receivable, Current, Allowance for Credit Loss	Changes to allowance for credit losses for the three months ended March 31, 2023 and 2022, respectively, were as follows (in thousands): Balance at Beginning of Year Additions Charged to Costs and Expenses Recoveries and Other Additions Write-offs and Other Deductions Balance at March 31, 2023 $ 2,953 $ 3,703 $ 641 $ ( 1,866 ) $ 5,431 2022 $ 2,113 $ 3,416 $ 655 $ ( 1,698 ) $ 4,486
Materials, Supplies and Fuel	The following amounts by major classification are included in Materials, supplies and fuel on the accompanying Consolidated Balance Sheets (in thousands) as of: March 31, 2023 December 31, 2022 Materials and supplies $ 102,328 $ 99,734 Fuel - Electric Utilities 6,808 3,115 Natural gas in storage 20,824 104,572 Total materials, supplies and fuel $ 129,960 $ 207,421
Schedule of Accrued Liabilities	The following amounts by major classification are included in Accrued liabilities on the accompanying Consolidated Balance Sheets (in thousands) as of: March 31, 2023 December 31, 2022 Accrued employee compensation, benefits and withholdings $ 48,555 $ 62,890 Accrued property taxes 54,694 52,430 Customer deposits and prepayments 42,124 47,655 Accrued interest 47,928 33,798 Other (none of which is individually significant) 35,560 46,684 Total accrued liabilities $ 228,861 $ 243,457
Schedule of Earnings Per Share Reconciliation	A reconciliation of share amounts used to compute earnings per share in the accompanying Consolidated Statements of Income was as follows (in thousands, except per share amounts): Three Months Ended March 31, 2023 2022 Net income available for common stock $ 114,084 $ 117,526 Weighted average shares - basic 66,036 64,565 Dilutive effect of: Equity compensation 96 156 Weighted average shares - diluted 66,132 64,721 Earnings per share of common stock: Earnings per share, Basic $ 1.73 $ 1.82 Earnings per share, Diluted $ 1.73 $ 1.82
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The following securities were excluded from the diluted earnings per share computation because of their anti-dilutive nature (in thousands): Three Months Ended March 31, 2023 2022 Equity compensation 53 - Anti-dilutive shares 53 -

Regulatory Matters (Tables)

Regulatory Matters (Tables)	3 Months Ended
	Mar. 31, 2023
Regulated Operations [Abstract]
Schedule of Regulatory Assets and Liabilities	We had the following regulatory assets and liabilities (in thousands): As of As of March 31, 2023 December 31, 2022 Regulatory assets Winter Storm Uri (a) $ 253,835 $ 347,980 Deferred energy and fuel cost adjustments (b) 79,020 72,580 Deferred gas cost adjustments (b) 16,047 12,147 Gas price derivatives (b) - 8,793 Deferred taxes on AFUDC (b) 7,482 7,333 Employee benefit plans and related deferred taxes (c) 88,710 89,259 Environmental (b) 1,341 1,343 Loss on reacquired debt (b) 18,764 19,213 Deferred taxes on flow through accounting (b) 74,022 69,529 Decommissioning costs (b) 2,850 3,472 Other regulatory assets (b) 19,798 21,332 Total regulatory assets 561,869 652,981 Less current regulatory assets ( 214,838 ) ( 260,312 ) Regulatory assets, non-current $ 347,031 $ 392,669 Regulatory liabilities Deferred energy and gas costs (b) $ 106,030 $ 41,722 Employee benefit plan costs and related deferred taxes (c) 33,839 34,258 Cost of removal (b) 177,453 175,614 Excess deferred income taxes (c) 248,126 254,833 Other regulatory liabilities (c) 11,613 12,146 Total regulatory liabilities 577,061 518,573 Less current regulatory liabilities ( 110,100 ) ( 46,013 ) Regulatory liabilities, non-current $ 466,961 $ 472,560 (a) Timing of Winter Storm Uri incremental cost recovery and associated carrying costs vary by jurisdiction. (b) Recovery or repayment of costs, but we are not 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.

Revenue (Tables)

Revenue (Tables)	3 Months Ended
	Mar. 31, 2023
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following tables depict the disaggregation of revenue, including intercompany revenue, from contracts with customers by customer type and timing of revenue recognition for each of the reportable segments for the three months ended March 31, 2023 and 2022. Sales tax and other similar taxes are excluded from revenues. Three Months Ended March 31, 2023 Electric Utilities Gas Utilities Inter-company Revenues Total Customer types: (in thousands) Retail $ 174,903 $ 635,545 $ - $ 810,448 Transportation - 52,843 ( 115 ) 52,728 Wholesale 9,398 - - 9,398 Market - off-system sales 16,124 281 - 16,405 Transmission/Other 17,404 10,023 ( 4,351 ) 23,076 Revenue from contracts with customers $ 217,829 $ 698,692 $ ( 4,466 ) $ 912,055 Other revenues 880 8,224 - 9,104 Total revenues $ 218,709 $ 706,916 $ ( 4,466 ) $ 921,159 Timing of revenue recognition: Services transferred at a point in time $ 8,657 $ - $ - $ 8,657 Services transferred over time 209,172 698,692 ( 4,466 ) 903,398 Revenue from contracts with customers $ 217,829 $ 698,692 $ ( 4,466 ) $ 912,055 Three Months Ended March 31, 2022 Electric Utilities Gas Utilities Inter-company Revenues Total Customer types: (in thousands) Retail $ 172,806 $ 561,013 $ - $ 733,819 Transportation - 49,523 ( 99 ) 49,424 Wholesale 10,275 - - 10,275 Market - off-system sales 7,154 238 - 7,392 Transmission/Other 15,433 9,575 ( 4,149 ) 20,859 Revenue from contracts with customers $ 205,668 $ 620,349 $ ( 4,248 ) $ 821,769 Other revenues 870 1,043 ( 112 ) 1,801 Total revenues $ 206,538 $ 621,392 $ ( 4,360 ) $ 823,570 Timing of revenue recognition: Services transferred at a point in time $ 7,113 $ - $ - $ 7,113 Services transferred over time 198,555 620,349 ( 4,248 ) 814,656 Revenue from contracts with customers $ 205,668 $ 620,349 $ ( 4,248 ) $ 821,769

Financing (Tables)

Financing (Tables)	3 Months Ended
	Mar. 31, 2023
Debt Disclosure [Abstract]
Schedule of Short-term Debt	Our Revolving Credit Facility and CP Program, which are classified as Notes payable on the Consolidated Balance Sheets, had the following borrowings, outstanding letters of credit, and available capacity (dollars in thousands): March 31, 2023 December 31, 2022 Amount outstanding $ — $ 535,600 Letters of credit (a) $ 2,401 $ 24,626 Available capacity $ 747,599 $ 189,774 Weighted average interest rates N/A 4.88 % (a) Letters of credit are off-balance sheet commitments that reduce the borrowing capacity available on our corporate Revolving Credit Facility . Revolving Credit Facility and CP Program borrowing activity was as follows (dollars in thousands): Three Months Ended March 31, 2023 2022 Maximum amount outstanding (based on daily outstanding balances) $ 548,700 $ 429,000 Average amount outstanding (based on daily outstanding balances) $ 331,268 $ 360,823 Weighted average interest rates 4.91 % 0.44 %
Credit Facility and Short Term Debt Covenants	We were in compliance with our covenants at March 31, 2023, as shown below: As of March 31, 2023 Covenant Requirement Consolidated Indebtedness to Capitalization Ratio 59.1 % Less than 65 %
Summary of ATM Activity	ATM activity was as follows (net proceeds and issuance costs in millions): Three Months Ended March 31, 2023 2022 Proceeds, (net of issuance costs of $( 0.3 ), $( 0.0 ) respectively) $ 27.4 $ 3.8 Average price per share $ 62.21 $ 68.79 Number of shares issued 445,578 55,707

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2023
Earnings Per Share [Abstract]
Schedule of Earnings Per Share Reconciliation	A reconciliation of share amounts used to compute earnings per share in the accompanying Consolidated Statements of Income was as follows (in thousands, except per share amounts): Three Months Ended March 31, 2023 2022 Net income available for common stock $ 114,084 $ 117,526 Weighted average shares - basic 66,036 64,565 Dilutive effect of: Equity compensation 96 156 Weighted average shares - diluted 66,132 64,721 Earnings per share of common stock: Earnings per share, Basic $ 1.73 $ 1.82 Earnings per share, Diluted $ 1.73 $ 1.82
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The following securities were excluded from the diluted earnings per share computation because of their anti-dilutive nature (in thousands): Three Months Ended March 31, 2023 2022 Equity compensation 53 - Anti-dilutive shares 53 -

Risk Management And Derivativ_2

Risk Management And Derivatives (Tables)	3 Months Ended
	Mar. 31, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Contract or notional amounts and terms of marketing activities and derivative commodity instruments	The contract or notional amounts and terms of the electric and natural gas derivative commodity instruments held at our Utilities are composed of both long and short positions. We had the following net long positions as of: March 31, 2023 December 31, 2022 Notional Amounts (MMBtus) Maximum Term (months) (a) Notional Amounts (MMBtus) Maximum Term (months) (a) Natural gas futures purchased - N/A 630,000 3 Natural gas options purchased, net - N/A 1,790,000 3 Natural gas basis swaps purchased - N/A 900,000 3 Natural gas over-the-counter swaps, net (b) 3,270,000 26 4,460,000 24 Natural gas physical contracts, net (c) 3,881,190 12 17,864,412 12 (a) Term reflects the maximum forward period hedged. (b) As of March 31, 2023 , 574,800 MMBtus of natural gas over-the-counter swaps purchases were designated as cash flow hedges. (c) Volumes exclude derivative contracts that qualify for the normal purchases and normal sales exception permitted by GAAP.
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	The following table presents the fair value and balance sheet classification of our derivative instruments (in thousands) as of: Balance Sheet Location March 31, December 31, Derivatives designated as hedges: Asset derivative instruments: Current commodity derivatives Derivative assets, current $ - $ 118 Noncurrent commodity derivatives Other assets, non-current - 198 Liability derivative instruments: Current commodity derivatives Derivative liabilities, current ( 543 ) ( 1,703 ) Noncurrent commodity derivatives Other assets, non-current ( 2 ) - Total derivatives designated as hedges $ ( 545 ) $ ( 1,387 ) Derivatives not designated as hedges: Asset derivative instruments: Current commodity derivatives Derivative assets, current $ 153 $ 464 Noncurrent commodity derivatives Other assets, non-current 111 337 Liability derivative instruments: Current commodity derivatives Derivative liabilities, current ( 1,186 ) ( 4,897 ) Noncurrent commodity derivatives Other deferred credits and other liabilities ( 20 ) ( 18 ) Total derivatives not designated as hedges $ ( 942 ) $ ( 4,114 )
Derivative Instruments, Gain (Loss)	The impacts of cash flow hedges on our Consolidated Statements of Comprehensive Income and Consolidated Statements of Income are presented below for the three months ended March 31, 2023 and 2022. Note that this presentation does not reflect the gains or losses arising from the underlying physical transactions; therefore, it is not indicative of the economic profit or loss we realized when the underlying physical and financial transactions were settled. Three Months Ended Three Months Ended 2023 2022 2023 2022 Derivatives in Cash Flow Hedging Relationships Amount of Gain/(Loss) Recognized in OCI Location on the Consolidated Statements of Income Amount of Gain/(Loss) Reclassified from AOCI into Income (in thousands) (in thousands) Interest rate swaps $ 713 $ 713 Interest expense $ ( 713 ) $ ( 713 ) Commodity derivatives 827 ( 867 ) Fuel, purchased power and cost of natural gas sold ( 1,950 ) 2,254 Total $ 1,540 $ ( 154 ) $ ( 2,663 ) $ 1,541 As of March 31, 2023, $ 3.6 million of net losses related to our interest rate swaps and commodity derivatives are expected to be reclassified from AOCI into earnings within the next 12 months. As market prices fluctuate, estimated and actual realized gains or losses will change during future periods. Derivatives Not Designated as Hedge Instruments The following table summarizes the impacts of derivative instruments not designated as hedge instruments on our Consolidated Statements of Income for the three months ended March 31, 2023 and 2022. Note that this presentation does not reflect the expected gains or losses arising from the underlying physical transactions; therefore, it is not indicative of the economic profit or loss we realized when the underlying physical and financial transactions were settled. Three Months Ended March 31, 2023 2022 Derivatives Not Designated as Hedging Instruments Location of Gain/(Loss) on Derivatives Recognized in Income Amount of Gain/(Loss) on Derivatives Recognized in Income Commodity derivatives - Natural Gas Fuel, purchased power and cost of natural gas sold $ ( 3,094 ) $ 3,494 $ ( 3,094 ) $ 3,494

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2023
Fair Value Disclosures [Abstract]
Schedule of Fair Value Hierarchy, Measured on Recurring Basis	The following tables set forth, by level within the fair value hierarchy, our gross assets and gross liabilities and related offsetting of cash collateral and contractual netting rights as permitted by GAAP that were accounted for at fair value on a recurring basis for derivative instruments. As of March 31, 2023 Level 1 Level 2 Level 3 Cash Collateral and Counterparty Netting (a) Total (in thousands) Assets: Commodity derivatives - Gas Utilities $ - $ 264 $ - $ - $ 264 Total $ - $ 264 $ - $ - $ 264 Liabilities: Commodity derivatives - Gas Utilities $ - $ 1,751 $ - $ - $ 1,751 Total $ - $ 1,751 $ - $ - $ 1,751 (a) As of March 31, 2023, we had no commodity derivative assets or liabilities, or related gross collateral amounts, that were subject to master netting agreements. As of December 31, 2022 Level 1 Level 2 Level 3 Cash Collateral and Counterparty Netting (a) Total (in thousands) Assets: Commodity derivatives - Gas Utilities $ - $ 5,407 $ - $ ( 4,290 ) $ 1,117 Total $ - $ 5,407 $ - $ ( 4,290 ) $ 1,117 Liabilities: Commodity derivatives - Gas Utilities $ - $ 11,455 $ - $ ( 4,837 ) $ 6,618 Total $ - $ 11,455 $ - $ ( 4,837 ) $ 6,618 (a) As of December 31, 2022 , $ 4.3 million of our commodity derivative assets and $ 4.8 million of our commodity derivative liabilities, as well as related gross collateral amounts, were subject to master netting agreements.
Fair Value, by Balance Sheet Grouping	The following table presents the carrying amounts and fair values of financial instruments not recorded at fair value on the Consolidated Balance Sheets (in thousands) as of: March 31, 2023 December 31, 2022 Carrying Amount Fair Value Carrying Amount Fair Value Long-term debt, including current maturities (a) $ 4,479,409 $ 4,205,369 $ 4,132,340 $ 3,760,848 (a) 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. Carrying amount of long-term debt is net of deferred financing costs.

Other Comprehensive Income (Tab

Other Comprehensive Income (Tables)	3 Months Ended
	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Reclassification out of Accumulated Other Comprehensive Income	The following table details reclassifications out of AOCI and into Net income. The amounts in parentheses below indicate decreases to Net income in the Consolidated Statements of Income for the period, net of tax (in thousands): Amount Reclassified from AOCI Location on the Consolidated Statements of Income Three Months Ended March 31, 2023 2022 Gains and (losses) on cash flow hedges: Interest rate swaps Interest expense $ ( 713 ) $ ( 713 ) Commodity contracts Fuel, purchased power and cost of natural gas sold ( 1,950 ) 2,254 $ ( 2,663 ) $ 1,541 Income tax Income tax expense 616 ( 375 ) Total reclassification adjustments related to cash flow hedges, net of tax $ ( 2,047 ) $ 1,166 Amortization of components of defined benefit plans: Prior service cost Operations and maintenance $ - $ 24 Actuarial gain (loss) Operations and maintenance ( 44 ) ( 188 ) $ ( 44 ) $ ( 164 ) Income tax Income tax expense 16 39 Total reclassification adjustments related to defined benefit plans, net of tax $ ( 28 ) $ ( 125 ) Total reclassifications $ ( 2,075 ) $ 1,041
Schedule of Accumulated Other Comprehensive Income (Loss)	Balances by classification included within AOCI, net of tax on the accompanying Consolidated Balance Sheets were as follows (in thousands): Derivatives Designated as Cash Flow Hedges Interest Rate Swaps Commodity Derivatives Employee Benefit Plans Total As of December 31, 2022 $ ( 8,255 ) $ ( 1,200 ) $ ( 6,112 ) $ ( 15,567 ) Other comprehensive income (loss) before reclassifications - ( 855 ) - ( 855 ) Amounts reclassified from AOCI 563 1,484 28 2,075 As of March 31, 2023 $ ( 7,692 ) $ ( 571 ) $ ( 6,084 ) $ ( 14,347 ) Derivatives Designated as Cash Flow Hedges Interest Rate Swaps Commodity Derivatives Employee Benefit Plans Total As of December 31, 2021 $ ( 10,384 ) $ 1,476 $ ( 11,176 ) $ ( 20,084 ) Other comprehensive income (loss) before reclassifications - 1,047 - 1,047 Amounts reclassified from AOCI 536 ( 1,702 ) 125 ( 1,041 ) As of March 31, 2022 $ ( 9,848 ) $ 821 $ ( 11,051 ) $ ( 20,078 )

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	3 Months Ended
	Mar. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Components of Net Periodic Benefit Cost	The components of net periodic expense were as follows (in thousands): Defined Benefit Pension Plan Supplemental Non-qualified Defined Benefit Plans Non-pension Defined Benefit Postretirement Healthcare Plan Three Months Ended March 31, 2023 2022 2023 2022 2023 2022 Service cost $ 614 $ 982 $ 914 $ ( 392 ) $ 381 $ 492 Interest cost 4,381 2,705 369 208 594 321 Expected return on plan assets ( 4,672 ) ( 4,631 ) - - ( 56 ) ( 31 ) Net amortization of prior service costs ( 17 ) ( 17 ) - - 10 ( 72 ) Recognized net actuarial loss (gain) 498 1,523 8 69 ( 3 ) 16 Net periodic expense (benefit) $ 804 $ 562 $ 1,291 $ ( 115 ) $ 926 $ 726
Schedule of Employer Contribution to Employee Benefit Plans	Contributions made in the first three months of 2023 and anticipated contributions for 2023 and 2024 are as follows (in thousands): Contributions Made Additional Contributions Contributions Three Months Ended March 31, 2023 Anticipated for 2023 Anticipated for 2024 Defined Benefit Pension Plan $ - $ - $ - Non-pension Defined Benefit Postretirement Healthcare Plan $ 1,230 $ 3,690 $ 4,556 Supplemental Non-qualified Defined Benefit and Defined Contribution Plans $ 558 $ 1,673 $ 2,410

Business Segment Information (T

Business Segment Information (Tables)	3 Months Ended
	Mar. 31, 2023
Segment Reporting Information, Additional Information [Abstract]
Schedule of Segment Reporting Information, by Segment	Segment information was as follows (in thousands): Total assets (net of intercompany eliminations) as of: March 31, 2023 December 31, 2022 Electric Utilities $ 3,922,496 $ 3,929,721 Gas Utilities 5,419,216 5,578,282 Corporate and Other 118,424 110,227 Total assets $ 9,460,136 $ 9,618,230 External Operating Revenue Inter-company Operating Revenue Three Months Ended March 31, 2023 Contract Customers Other Revenues Contract Customers Other Revenues Total Revenues Segment: Electric Utilities $ 215,012 $ 881 $ 2,816 $ - $ 218,709 Gas Utilities 697,043 8,223 1,650 - 706,916 Inter-company eliminations - - ( 4,466 ) - ( 4,466 ) Total $ 912,055 $ 9,104 $ - $ - $ 921,159 External Operating Revenue Inter-company Operating Revenue Three Months Ended March 31, 2022 Contract Customers Other Revenues Contract Customers Other Revenues Total Revenues Segment: Electric Utilities $ 202,739 $ 870 $ 2,929 $ - $ 206,538 Gas Utilities 619,030 931 1,319 112 621,392 Inter-company eliminations - - ( 4,248 ) ( 112 ) ( 4,360 ) Total $ 821,769 $ 1,801 $ - $ - $ 823,570 Three Months Ended March 31, 2023 2022 Operating income (loss): Electric Utilities $ 61,060 $ 50,746 Gas Utilities 114,625 123,540 Corporate and Other ( 802 ) ( 933 ) Operating income 174,883 173,353 Interest expense, net ( 43,504 ) ( 38,545 ) Other income, net 674 704 Income tax expense ( 14,673 ) ( 14,488 ) Net income 117,380 121,024 Net income attributable to non-controlling interest ( 3,296 ) ( 3,498 ) Net income available for common stock $ 114,084 $ 117,526

Selected Balance Sheet Inform_2

Selected Balance Sheet Information (Tables)	3 Months Ended
	Mar. 31, 2023
Selected Balance Sheet Information [Abstract]
Account Receivable Schedule	Following is a summary of Accounts receivable, net included in the accompanying Consolidated Balance Sheets (in thousands) as of: March 31, 2023 December 31, 2022 Billed Accounts Receivable $ 327,949 $ 267,571 Unbilled Revenue 154,571 243,574 Less: Allowance for Credit Losses ( 5,431 ) ( 2,953 ) Account Receivable, net $ 477,089 $ 508,192
Financing Receivable, Current, Allowance for Credit Loss	Changes to allowance for credit losses for the three months ended March 31, 2023 and 2022, respectively, were as follows (in thousands): Balance at Beginning of Year Additions Charged to Costs and Expenses Recoveries and Other Additions Write-offs and Other Deductions Balance at March 31, 2023 $ 2,953 $ 3,703 $ 641 $ ( 1,866 ) $ 5,431 2022 $ 2,113 $ 3,416 $ 655 $ ( 1,698 ) $ 4,486
Materials, Supplies and Fuel	The following amounts by major classification are included in Materials, supplies and fuel on the accompanying Consolidated Balance Sheets (in thousands) as of: March 31, 2023 December 31, 2022 Materials and supplies $ 102,328 $ 99,734 Fuel - Electric Utilities 6,808 3,115 Natural gas in storage 20,824 104,572 Total materials, supplies and fuel $ 129,960 $ 207,421
Schedule of Accrued Liabilities	The following amounts by major classification are included in Accrued liabilities on the accompanying Consolidated Balance Sheets (in thousands) as of: March 31, 2023 December 31, 2022 Accrued employee compensation, benefits and withholdings $ 48,555 $ 62,890 Accrued property taxes 54,694 52,430 Customer deposits and prepayments 42,124 47,655 Accrued interest 47,928 33,798 Other (none of which is individually significant) 35,560 46,684 Total accrued liabilities $ 228,861 $ 243,457

Regulatory Matters_ Regulatory

Regulatory Matters: Regulatory Matters (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Regulatory assets	$ 561,869	$ 652,981
Regulatory assets, current	(214,838)	(260,312)
Regulatory assets, non-current	347,031	392,669
Regulatory liabilities	577,061	518,573
Regulatory liabilities, current	(110,100)	(46,013)
Regulatory liabilities, non-current	466,961	472,560
Deferred energy and gas costs
Regulatory liabilities	106,030	41,722
Employee benefit plan costs and related deferred taxes
Regulatory liabilities	33,839	34,258
Cost of removal
Regulatory liabilities	177,453	175,614
Excess deferred income taxes
Regulatory liabilities	248,126	254,833
Other regulatory liabilities
Regulatory liabilities	11,613	12,146
Storm Costs
Regulatory assets	253,835	347,980
Deferred energy and gas costs
Regulatory assets	79,020	72,580
Deferred gas cost adjustments
Regulatory assets	16,047	12,147
Gas price derivatives
Regulatory assets	0	8,793
Regulatory liabilities	100
Deferred taxes on AFUDC
Regulatory assets	7,482	7,333
Employee benefit plans and related deferred taxes
Regulatory assets	88,710	89,259
Environmental
Regulatory assets	1,341	1,343
Loss on reacquired debt
Regulatory assets	18,764	19,213
Deferred taxes on flow through accounting
Regulatory assets	74,022	69,529
Decommissioning costs
Regulatory assets	2,850	3,472
Other regulatory assets
Regulatory assets	$ 19,798	$ 21,332

Regulatory Matters_ Gas Utiliti

Regulatory Matters: Gas Utilities Regulatory Activity (Details) $ in Millions	Apr. 07, 2023 USD ($)	Jan. 26, 2023 USD ($)	Jun. 01, 2022 mi
Colorado Public Utilities Commission (CPUC) | Black Hills Energy - Colorado Gas | Settlement agreement reached with CPUC Staff and various intervenors, subject to the review and approval by an Administrative Law Judge and the CPUC.
Public Utilities, General Disclosures [Line Items]
Public Utilities Amount of System Safety and Integrity Rider Moved to Base Rates and Termination of the System Safety and Integrity Rider	$ 8.3
Colorado Public Utilities Commission (CPUC) | Black Hills Energy - Colorado Gas | Settlement Reached with the Regulatory Agency
Public Utilities, General Disclosures [Line Items]
Weighted average cost of capital	6.93%
Public Utilities, Approved Rate Increase (Decrease), Amount	$ 8.2
Colorado Public Utilities Commission (CPUC) | Black Hills Energy - Colorado Gas | Settlement Reached with the Regulatory Agency | Minimum
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Equity Capital Structure, Percentage	50%
Public Utilities, Approved Debt Capital Structure, Percentage	50%
Public Utilities, Approved Return on Equity, Percentage	9.50%
Colorado Public Utilities Commission (CPUC) | Black Hills Energy - Colorado Gas | Settlement Reached with the Regulatory Agency | Maximum
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Equity Capital Structure, Percentage	52%
Public Utilities, Approved Debt Capital Structure, Percentage	48%
Public Utilities, Approved Return on Equity, Percentage	9.70%
Wyoming Public Service Commission | Wyoming Electric | Rate Review Filed with the Regulatory Agency
Public Utilities, General Disclosures [Line Items]
Public Utilities - Length of Electric Distribution Lines to Receive Infrastructure Investments | mi			1,330
Public Utilities - Length of Electric Transmission Lines to Receive Infrastructure Investments | mi			59
Wyoming Public Service Commission | Wyoming Electric | Settlement Reached with the Regulatory Agency
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Equity Capital Structure, Percentage		52%
Public Utilities, Approved Debt Capital Structure, Percentage		48%
Public Utilities, Approved Return on Equity, Percentage		9.75%
Public Utilities, Approved Rate Increase (Decrease), Amount		$ 8.7

Revenue_ Disaggregation of Reve

Revenue: Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Revenue from contracts with customers	$ 912,055	$ 821,769
Revenue	921,159	823,570
Retail - Electric , Natural Gas and Coal
Revenue from contracts with customers	810,448	733,819
Transportation
Revenue from contracts with customers	52,728	49,424
Wholesale
Revenue from contracts with customers	9,398	10,275
Market - off-system sales
Revenue from contracts with customers	16,405	7,392
Transmission/Other
Revenue from contracts with customers	23,076	20,859
Other revenues
Revenue	9,104	1,801
Services transferred at a point in time
Revenue from contracts with customers	8,657	7,113
Services transferred over time
Revenue from contracts with customers	903,398	814,656
Electric Utilities
Revenue from contracts with customers	217,829	205,668
Revenue	218,709	206,538
Electric Utilities | Retail - Electric , Natural Gas and Coal
Revenue from contracts with customers	174,903	172,806
Electric Utilities | Transportation
Revenue from contracts with customers	0	0
Electric Utilities | Wholesale
Revenue from contracts with customers	9,398	10,275
Electric Utilities | Market - off-system sales
Revenue from contracts with customers	16,124	7,154
Electric Utilities | Transmission/Other
Revenue from contracts with customers	17,404	15,433
Electric Utilities | Other revenues
Revenue	880	870
Electric Utilities | Services transferred at a point in time
Revenue from contracts with customers	8,657	7,113
Electric Utilities | Services transferred over time
Revenue from contracts with customers	209,172	198,555
Gas Utilities
Revenue from contracts with customers	698,692	620,349
Revenue	706,916	621,392
Gas Utilities | Retail - Electric , Natural Gas and Coal
Revenue from contracts with customers	635,545	561,013
Gas Utilities | Transportation
Revenue from contracts with customers	52,843	49,523
Gas Utilities | Wholesale
Revenue from contracts with customers	0	0
Gas Utilities | Market - off-system sales
Revenue from contracts with customers	281	238
Gas Utilities | Transmission/Other
Revenue from contracts with customers	10,023	9,575
Gas Utilities | Other revenues
Revenue	8,224	1,043
Gas Utilities | Services transferred at a point in time
Revenue from contracts with customers	0	0
Gas Utilities | Services transferred over time
Revenue from contracts with customers	698,692	620,349
Intercompany Eliminations
Revenue from contracts with customers	(4,466)	(4,248)
Revenue	(4,466)	(4,360)
Intercompany Eliminations | Retail - Electric , Natural Gas and Coal
Revenue from contracts with customers	0	0
Intercompany Eliminations | Transportation
Revenue from contracts with customers	(115)	(99)
Intercompany Eliminations | Wholesale
Revenue from contracts with customers	0	0
Intercompany Eliminations | Market - off-system sales
Revenue from contracts with customers	0	0
Intercompany Eliminations | Transmission/Other
Revenue from contracts with customers	(4,351)	(4,149)
Intercompany Eliminations | Other revenues
Revenue	0	(112)
Intercompany Eliminations | Services transferred at a point in time
Revenue from contracts with customers	0	0
Intercompany Eliminations | Services transferred over time
Revenue from contracts with customers	$ (4,466)	$ (4,248)

Financing - Schedule of Short-t

Financing - Schedule of Short-term Debt and Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Short-Term Debt [Line Items]
Amount outstanding	$ 0		$ 535,600
Revolving Credit Facility | Commercial Paper
Short-Term Debt [Line Items]
Amount outstanding	0		535,600
Letters of Credit	2,401		24,626
Available capacity	747,599		$ 189,774
Weighted average interest rates			4.88%
Maximum amount outstanding (based on daily outstanding balances)	548,700	$ 429,000
Average amount outstanding (based on daily outstanding balances)	$ 331,268	$ 360,823
Weighted average interest rates	4.91%	0.44%

Financing_ Long-Term Debt (Addi

Financing: Long-Term Debt (Additional Information) (Details) - Senior Unsecured Notes Due 2028 $ in Millions	Mar. 07, 2023 USD ($)
Debt Instrument [Line Items]
Stated interest rate (percent)	5.95%
Debt Instrument, Term	5 years
Less unamortized deferred financing costs	$ 4.2
Corporate, Non-Segment
Debt Instrument [Line Items]
Proceeds from Issuance of Debt	$ 350

Financing_ Debt Covenants (Deta

Financing: Debt Covenants (Details)	Mar. 31, 2023
Debt Instrument [Line Items]
Consolidated Indebtedness to Capitalization Ratio	0.591
Maximum
Debt Instrument [Line Items]
Consolidated Indebtedness to Capitalization Ratio	0.65

Financing_ Debt Covenants (Addi

Financing: Debt Covenants (Additional Information) (Details) - Maximum	Mar. 31, 2023
Line of Credit Facility [Line Items]
Consolidated Indebtedness to Capitalization Ratio	0.65
Wyoming Electric
Line of Credit Facility [Line Items]
Consolidated Indebtedness to Capitalization Ratio	0.60

Financing_ At-the-Market Equity

Financing: At-the-Market Equity Offering Program (Details) - USD ($)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Number of shares issued	445,578	55,707
Number of shares issued	34,040
Common Stock
Proceeds, (net of issuance costs)	$ 27,400	$ 3,800
Average price per share	$ 62.21	$ 68.79
Payments of Stock Issuance Costs	$ (300,000)	$ 0

Earnings Per Share - Earnings P

Earnings Per Share - Earnings Per Share Reconciliation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Earnings Per Share [Abstract]
Net income available for common stock	$ 114,084	$ 117,526
Weighted average shares - Basic (in shares)	66,036	64,565
Dilutive effect of:
Equity compensation (in shares)	96	156
Weighted average shares - diluted (in shares)	66,132	64,721
Earnings per share, Basic (usd per share)	$ 1.73	$ 1.82
Earnings per share, Diluted (usd per share)	$ 1.73	$ 1.82

Earnings Per Share - Schedule o

Earnings Per Share - Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share
Anti-dilutive shares (in shares)	53	0
Share-Based Payment Arrangement [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share
Anti-dilutive shares (in shares)	53	0

Property, Plant and Equipment (

Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Total gross property, plant and equipment	$ 8,466,173	$ 8,374,790
Less accumulated depreciation and depletion	(1,628,772)	(1,576,842)
Property, plant and equipment of variable interest entities, net	$ 6,837,401	$ 6,797,948

Risk Management and Derivativ_3

Risk Management and Derivatives: Utilities (Details) $ in Millions		3 Months Ended	12 Months Ended
		Mar. 31, 2023 USD ($) MMBTU	Dec. 31, 2022 MMBTU
Derivative [Line Items]
Credit Risk Derivative Liabilities, at Fair Value | $		$ 0.6
Natural Gas, Distribution | Cash Flow Hedging
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount		574,800
Natural Gas, Distribution | Natural gas futures purchased
Derivative [Line Items]
Derivative, Remaining Maturity	[1]		3 months
Natural Gas, Distribution | Natural gas futures purchased | Long
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount			630,000
Natural Gas, Distribution | Natural gas options purchased, net
Derivative [Line Items]
Derivative, Remaining Maturity	[1]		3 months
Natural Gas, Distribution | Natural gas options purchased, net | Long
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount			1,790,000
Natural Gas, Distribution | Natural gas basis swaps purchased
Derivative [Line Items]
Derivative, Remaining Maturity	[1]		3 months
Natural Gas, Distribution | Natural gas basis swaps purchased | Long
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount			900,000
Natural Gas, Distribution | Natural gas over-the-counter swaps, net
Derivative [Line Items]
Derivative, Remaining Maturity	[1],[2]	26 months	24 months
Natural Gas, Distribution | Natural gas over-the-counter swaps, net | Long
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	[2]	3,270,000	4,460,000
Natural Gas, Distribution | Natural gas physical contracts, net
Derivative [Line Items]
Derivative, Remaining Maturity	[1],[3]	12 months	12 months
Natural Gas, Distribution | Natural gas physical contracts, net | Long
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	[3]	3,881,190	17,864,412
[1] Term reflects the maximum forward period hedged. As of March 31, 2023 , 574,800 MMBtus of natural gas over-the-counter swaps purchases were designated as cash flow hedges. Volumes exclude derivative contracts that qualify for the normal purchases and normal sales exception permitted by GAAP.

Risk Management and Derivativ_4

Risk Management and Derivatives: Derivatives by Balance Sheet Classification (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	$ (545)	$ (1,387)
Commodity Contract | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	(942)	(4,114)
Derivative assets, current | Commodity Contract | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	118
Derivative assets, current | Commodity Contract | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	153	464
Other assets, non-current | Commodity Contract | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	198
Derivative Liability, Fair Value, Gross Liability	(2)
Other assets, non-current | Commodity Contract | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	111	337
Derivative liabilities, current | Commodity Contract | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	(543)	(1,703)
Derivative liabilities, current | Commodity Contract | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	(1,186)	(4,897)
Other deferred credits and other liabilities | Commodity Contract | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ (20)	$ (18)

Risk Management and Derivativ_5

Risk Management and Derivatives: Cash Flow Hedges (Details) - Cash Flow Hedging - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Interest rate swaps
Derivative [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	$ 3,600
Designated as Hedging Instrument
Derivative [Line Items]
Unrealized Gain (Loss) on Cash Flow Hedging Instruments	1,540	$ (154)
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ (2,663)	$ 1,541
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration]	Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest
Designated as Hedging Instrument | Interest rate swaps
Derivative [Line Items]
Unrealized Gain (Loss) on Cash Flow Hedging Instruments	$ 713	$ 713
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion	$ (713)	$ (713)
Derivative Instrument, Loss Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest Costs Incurred	Interest Costs Incurred
Designated as Hedging Instrument | Commodity Contract
Derivative [Line Items]
Unrealized Gain (Loss) on Cash Flow Hedging Instruments	$ 827	$ (867)
Derivative Instruments, Loss Reclassified from Accumulated OCI into Income, Effective Portion	$ (1,950)
Derivative Instruments, Gain Reclassified from Accumulated OCI into Income, Effective Portion		$ 2,254
Derivative Instrument, Gain Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration]	Fuel, Purchased Power and Cost of Gas Sold	Fuel, Purchased Power and Cost of Gas Sold

Risk Management and Derivativ_6

Risk Management and Derivatives: Derivatives Not Designated as Hedge Instruments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Derivative [Line Items]
Regulatory assets	$ 561,869		$ 652,981
Regulatory liabilities	577,061		518,573
Gas price derivatives
Derivative [Line Items]
Regulatory assets	0		$ 8,793
Regulatory liabilities	100
Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ (3,094)	$ 3,494
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Fuel, Purchased Power and Cost of Gas Sold	Fuel, Purchased Power and Cost of Gas Sold
Not Designated as Hedging Instrument | Natural Gas
Derivative [Line Items]
Derivative, Loss on Derivative	$ (3,094)
Derivative, Loss, Statement of Income or Comprehensive Income [Extensible Enumeration]	Fuel, Purchased Power and Cost of Gas Sold	Fuel, Purchased Power and Cost of Gas Sold
Derivative, Gain on Derivative		$ 3,494

Fair Value Measurements_ Schedu

Fair Value Measurements: Schedule of Fair Values (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Derivative Asset, Current	Derivative Asset, Current
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Derivative Liability, Current	Derivative Liability, Current
Contract Subject to Master Netting
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Asset		$ 4,300
Derivative Liability, Fair Value, Gross Liability		4,800
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	$ 0	(4,290)
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	0	(4,837)
Fair Value, Measurements, Recurring | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Total	264	1,117
Derivative Liabilities, Total	1,751	6,618
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Total	0	0
Derivative Liabilities, Total	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Total	264	5,407
Derivative Liabilities, Total	1,751	11,455
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Total	0	0
Derivative Liabilities, Total	0	0
Fair Value, Measurements, Recurring | Gas Utilities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset	0	(4,290)
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	0	(4,837)
Fair Value, Measurements, Recurring | Gas Utilities | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	264	1,117
Derivative, Liabilities, Fair Value Disclosure	1,751	6,618
Fair Value, Measurements, Recurring | Gas Utilities | Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0	0
Derivative, Liabilities, Fair Value Disclosure	0	0
Fair Value, Measurements, Recurring | Gas Utilities | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	264	5,407
Derivative, Liabilities, Fair Value Disclosure	1,751	11,455
Fair Value, Measurements, Recurring | Gas Utilities | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0	0
Derivative, Liabilities, Fair Value Disclosure	$ 0	$ 0

Fair Value Measurements_ Other

Fair Value Measurements: Other Fair Value Measurements (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt	$ 4,479,409	$ 4,132,340
Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt	$ 4,205,369	$ 3,760,848

Other Comprehensive Income_ Rec

Other Comprehensive Income: Reclassification Out of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Interest expense	$ 44,065	$ 38,821
Fuel, purchased power and cost of natural gas sold	526,267	436,926
Operations and maintenance	140,988	136,132
Income Tax Expense (Benefit)	(14,673)	(14,488)
Net income	117,380	121,024
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Operations and maintenance	0	24
Net income	(2,075)	1,041
Cash Flow Hedging | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income before income taxes	(2,663)	1,541
Income Tax Expense (Benefit)	616	(375)
Net income	(2,047)	1,166
Cash Flow Hedging | Reclassification out of Accumulated Other Comprehensive Income | Interest Rate Swap
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Interest expense	(713)	(713)
Cash Flow Hedging | Reclassification out of Accumulated Other Comprehensive Income | Commodity Contract
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Fuel, purchased power and cost of natural gas sold	(1,950)	2,254
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]
Operations and maintenance	(44)	(188)
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 before income taxes	(44)	(164)
Income Tax Expense (Benefit)	16	39
Net income	$ (28)	$ (125)

Other Comprehensive Income_ Acc

Other Comprehensive Income: Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start	$ (15,567)	$ (20,084)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End	(14,347)	(20,078)
Accumulated Defined Benefit Plans Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start	(6,112)	(11,176)
Other comprehensive income (loss), before reclassifications	0	0
Amounts reclassified from AOCI	28	125
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End	(6,084)	(11,051)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), before reclassifications	(855)	1,047
Accumulated Other Comprehensive Income (Loss) | Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from AOCI	2,075	(1,041)
Interest Rate Swap | Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start	(8,255)	(10,384)
Other comprehensive income (loss), before reclassifications	0	0
Amounts reclassified from AOCI	563	536
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End	(7,692)	(9,848)
Commodity Contract | Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start	(1,200)	1,476
Other comprehensive income (loss), before reclassifications	(855)	1,047
Amounts reclassified from AOCI	1,484	(1,702)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End	$ (571)	$ 821

Employee Benefit Plans_ Plan Co

Employee Benefit Plans: Plan Contributions (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($)
Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Estimated Future Employer Contributions in Next Fiscal Year	$ 0
Payment for Pension Benefits	0
Estimated Future Employer Contributions in Current Fiscal Year	0
Other Postretirement Benefits Plan
Defined Benefit Plan Disclosure [Line Items]
Estimated Future Employer Contributions in Next Fiscal Year	4,556
Payment for Pension Benefits	1,230
Estimated Future Employer Contributions in Current Fiscal Year	3,690
Supplemental Non-Qualified Defined Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Estimated Future Employer Contributions in Next Fiscal Year	2,410
Payment for Pension Benefits	558
Estimated Future Employer Contributions in Current Fiscal Year	$ 1,673

Employee Benefit Plans_ Compone

Employee Benefit Plans: Components of Net Periodic Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Service Cost	$ 614	$ 982
Interest cost	4,381	2,705
Expected return on assets	(4,672)	(4,631)
Net amortization of prior service cost	(17)	(17)
Recognized net actuarial loss (gain)	498	1,523
Net periodic expense (benefit)	804	562
Supplemental Employee Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Service Cost	914	(392)
Interest cost	369	208
Expected return on assets	0	0
Net amortization of prior service cost	0	0
Recognized net actuarial loss (gain)	8	69
Net periodic expense (benefit)	1,291	(115)
Other Postretirement Benefits Plan
Defined Benefit Plan Disclosure [Line Items]
Service Cost	381	492
Interest cost	594	321
Expected return on assets	(56)	(31)
Net amortization of prior service cost	10	(72)
Recognized net actuarial loss (gain)	(3)	16
Net periodic expense (benefit)	$ 926	$ 726

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Income Tax Disclosure [Line Items]
Income Tax Expense (Benefit)	$ 14,673	$ 14,488
Effective Tax Rate	11.10%	10.70%

Share-based Compensation Plans_

Share-based Compensation Plans: Compensation Related Costs, Share Based Payments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Share-Based Payment Arrangement [Abstract]
Stock compensation	$ 1,784	$ 3,638

Business Segment Information_ I

Business Segment Information: Information Relating to Segments Statement of Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Segment Reporting Information
Revenue from contracts with customers	$ 912,055	$ 821,769
Revenue	921,159	823,570
Fuel, purchased power and cost of natural gas sold	526,267	436,926
Depreciation, depletion and amortization	61,643	60,463
Operating income (loss)	174,883	173,353
Interest expense, net	(43,504)	(38,545)
Other income, net	674	704
Income tax (expense)	(14,673)	(14,488)
Net income	117,380	121,024
Net income attributable to non-controlling interest	(3,296)	(3,498)
Net income available for common stock	114,084	117,526
Electric Utilities
Segment Reporting Information
Revenue from contracts with customers	217,829	205,668
Revenue	218,709	206,538
Operating income (loss)	61,060	50,746
Gas Utilities
Segment Reporting Information
Revenue from contracts with customers	698,692	620,349
Revenue	706,916	621,392
Operating income (loss)	114,625	123,540
Corporate, Non-Segment
Segment Reporting Information
Operating income (loss)	(802)	(933)
Intercompany Eliminations
Segment Reporting Information
Revenue from contracts with customers	(4,466)	(4,248)
Revenue	(4,466)	(4,360)
Other revenues
Segment Reporting Information
Revenue	9,104	1,801
Other revenues | Electric Utilities
Segment Reporting Information
Revenue	880	870
Other revenues | Gas Utilities
Segment Reporting Information
Revenue	8,224	1,043
Other revenues | Intercompany Eliminations
Segment Reporting Information
Revenue	0	(112)
External Customers
Segment Reporting Information
Revenue from contracts with customers	912,055	821,769
External Customers | Electric Utilities
Segment Reporting Information
Revenue from contracts with customers	215,012	202,739
External Customers | Gas Utilities
Segment Reporting Information
Revenue from contracts with customers	697,043	619,030
External Customers | Other revenues
Segment Reporting Information
Revenue	9,104	1,801
External Customers | Other revenues | Electric Utilities
Segment Reporting Information
Revenue	881	870
External Customers | Other revenues | Gas Utilities
Segment Reporting Information
Revenue	8,223	931
Intercompany Customers
Segment Reporting Information
Revenue from contracts with customers	0	0
Intercompany Customers | Electric Utilities
Segment Reporting Information
Revenue from contracts with customers	2,816	2,929
Intercompany Customers | Gas Utilities
Segment Reporting Information
Revenue from contracts with customers	1,650	1,319
Intercompany Customers | Intercompany Eliminations
Segment Reporting Information
Revenue from contracts with customers	(4,466)	(4,248)
Intercompany Customers | Other revenues
Segment Reporting Information
Revenue	0	0
Intercompany Customers | Other revenues | Electric Utilities
Segment Reporting Information
Revenue	0	0
Intercompany Customers | Other revenues | Gas Utilities
Segment Reporting Information
Revenue	0	112
Intercompany Customers | Other revenues | Intercompany Eliminations
Segment Reporting Information
Revenue	$ 0	$ (112)

Business Segment Information_ S

Business Segment Information: Segment Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Segment Reporting, Asset Reconciling Item
Total Assets	$ 9,460,136	$ 9,618,230
Corporate and Other
Segment Reporting, Asset Reconciling Item
Total Assets	118,424	110,227
Electric Utilities
Segment Reporting, Asset Reconciling Item
Total Assets	3,922,496	3,929,721
Gas Utilities
Segment Reporting, Asset Reconciling Item
Total Assets	$ 5,419,216	$ 5,578,282

Selected Balance Sheet Inform_3

Selected Balance Sheet Information: Accounts Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Selected Balance Sheet Information [Abstract]
Billed Accounts Receivable	$ 327,949	$ 267,571
Unbilled Revenue	154,571	243,574
Less: Allowance for Credit Losses	(5,431)	(2,953)	$ (4,486)	$ (2,113)
Account Receivable, net	$ 477,089	$ 508,192

Selected Balance Sheet Inform_4

Selected Balance Sheet Information: Changes to Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Selected Balance Sheet Information [Abstract]
Balance at Beginning of Year	$ 2,953	$ 2,113
Additions Charged to Costs and Expenses	3,703	3,416
Recoveries and Other Additions	641	655
Write-offs and Other Deductions	(1,866)	(1,698)
Balance at End of Year	$ 5,431	$ 4,486

Selected Balance Sheet Inform_5

Selected Balance Sheet Information: Materials, Supplies, and Fuel Schedule (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Selected Balance Sheet Information [Abstract]
Materials and supplies	$ 102,328	$ 99,734
Fuel - Electric Utilities	6,808	3,115
Natural gas in storage	20,824	104,572
Total materials, supplies and fuel	$ 129,960	$ 207,421

Selected Balance Sheet Inform_6

Selected Balance Sheet Information: Accrued Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Selected Balance Sheet Information [Abstract]
Accrued employee compensation, benefits and withholdings	$ 48,555	$ 62,890
Accrued property taxes	54,694	52,430
Customer deposits and prepayments	42,124	47,655
Accrued interest	47,928	33,798
Other (none of which is individually significant)	35,560	46,684
Total accrued liabilities	$ 228,861	$ 243,457