CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Operating Activities:
Net income	$ 112,840	$ 87,045
Non-cash items included in net income:
Depreciation and amortization	203,650	198,272
Deferred income tax provision	(24,853)	(15,958)
Power and natural gas cost deferrals, net	86,408	(25,046)
Amortization of debt expense	1,578	2,431
Stock-based compensation expense	8,291	7,098
Equity-related AFUDC	(6,174)	(4,921)
Pension and other postretirement benefit expense	9,140	9,923
Other regulatory assets and liabilities	(20,973)	(12,582)
Other deferred debits and credits	25,811	31,058
Change in decoupling regulatory deferral	(22,872)	11,231
Realized and unrealized losses on assets	873	966
Other	(1,513)	(2,525)
Contributions to defined benefit pension plan	(10,000)	(10,000)
Cash paid for settlement of interest rate swap agreements		(409)
Cash received for settlement of interest rate swap agreements	4,397	7,869
Changes in certain current assets and liabilities:
Accounts and notes receivable	67,697	119,908
Inventory	(25,956)	(37,500)
Collateral for derivative instruments	17,581	144,163
Income taxes receivable	20,132	(1,417)
Other current assets	13,601	(22,941)
Accounts payable	(33,269)	(96,794)
Other current liabilities	17,818	3,435
Net cash provided by operating activities	444,207	393,306
Investing Activities:
Utility property capital expenditures (excluding equity-related AFUDC)	(405,428)	(359,277)
Investments made in equity and property	(7,574)	(12,000)
Proceeds from sale of investments		3,200
Other	2,990	(503)
Net cash used in investing activities	(410,012)	(368,580)
Financing Activities:
Net decrease in short-term borrowings	(61,750)	(241,500)
Proceeds from issuance of long-term debt	83,700	250,000
Maturity of long-term debt and finance leases	(2,550)	(15,926)
Issuance of common stock, net of issuance costs	35,743	88,165
Cash dividends paid	(112,475)	(105,163)
Other	(2,742)	(5,100)
Net cash used in financing activities	(60,074)	(29,524)
Net decrease in cash and cash equivalents	(25,879)	(4,798)
Cash and cash equivalents at beginning of period	35,003	13,428
Cash and cash equivalents at end of period	$ 9,124	$ 8,630