CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Operating Activities:
Net income	$ 94,353	$ 72,329
Non-cash items included in net income:
Depreciation and amortization	135,761	131,367
Deferred income tax provision	(23,004)	(20,565)
Power and natural gas cost deferrals, net	74,643	(31,559)
Amortization of debt expense	1,039	1,980
Stock-based compensation expense	6,350	5,460
Equity-related AFUDC	(3,830)	(3,172)
Pension and other postretirement benefit expense	5,942	6,693
Other regulatory assets and liabilities	(14,028)	(31,997)
Other deferred debits and credits	22,469	32,351
Change in decoupling regulatory deferral	(18,752)	14,383
Realized and unrealized loss (gain) on assets and investments	(294)	2,752
Other	1,831	(2,436)
Contributions to defined benefit pension plan	(6,666)	(6,666)
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	59,468	111,428
Inventory	(15,605)	(8,131)
Collateral for derivative instruments	18,453	116,602
Income taxes receivable	21,242	7,476
Other current assets	(81)	(20,228)
Accounts payable	(33,884)	(96,080)
Other current liabilities	(12,809)	(19,886)
Net cash provided by operating activities	316,995	269,561
Investing Activities:
Utility property capital expenditures (excluding equity-related AFUDC)	(251,207)	(226,746)
Issuance of notes receivable		(1,500)
Investments made in equity and property	(5,115)	(6,481)
Other	2,192	652
Net cash used in investing activities	(254,130)	(234,075)
Financing Activities:
Net decrease in short-term borrowings	(105,000)	(260,000)
Proceeds from issuance of long-term debt	83,700	250,000
Maturity of long-term debt and finance leases	(1,700)	(8,118)
Issuance of common stock, net of issuance costs	17,600	59,525
Cash dividends paid	(75,090)	(69,942)
Other	(2,731)	(4,675)
Net cash used in financing activities	(83,221)	(33,210)
Net increase (decrease) in cash and cash equivalents	(20,356)	2,276
Cash and cash equivalents at beginning of period	35,003	13,428
Cash and cash equivalents at end of period	$ 14,647	$ 15,704