Consolidated Statements Of Cash Flow - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Cash flows from operating activities:
Net income	$ 282,702	$ 281,667
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	169,455	157,522
Deferred income taxes	(34,711)	(13,810)
Provision for doubtful accounts	11,594	12,793
Stock-based compensation	6,950	5,471
Gain on sale of utility systems and other assets	(469)	(478)
Net change in receivables, deferred purchased gas costs, inventory and prepayments	300,648	6,742
Net change in payables, accrued interest, accrued taxes and other accrued liabilities	(90,739)	(4,222)
Pension and other postretirement benefits contributions		(14,564)
Other	(24,008)	(14,819)
Net cash flows from operating activities	621,422	416,302
Cash flows from investing activities:
Property, plant and equipment additions, including the debt component of allowance for funds used during construction of $2,587 and $3,013	(547,600)	(424,645)
Acquisitions of utility systems, net	(25,793)	(50,010)
Net proceeds from the sale of utility systems and other assets	613	485
Other	386	157
Net cash flows used in investing activities	(572,394)	(474,013)
Cash flows from financing activities:
Customers' advances and contributions in aid of construction	9,375	5,796
Repayments of customers' advances	(1,958)	(901)
Net proceeds (repayments) of short-term debt	(180,457)	(60,297)
Proceeds from long-term debt	384,715	770,376
Repayments of long-term debt	(136,604)	(464,585)
Change in cash overdraft position	3,795	(61,061)
Proceeds from issuance of common stock under dividend reinvestment plan	8,069	8,171
Proceeds from issuance of common stock from at-the-market sale agreement	19,294
Proceeds from exercised stock options	209	1,239
Repurchase of common stock	(3,953)	(1,027)
Dividends paid on common stock	(151,686)	(138,108)
Other	417	517
Net cash flows from (used in) financing activities	(48,784)	60,120
Net change in cash and cash equivalents	244	2,409
Cash and cash equivalents at beginning of period	11,398	10,567
Cash and cash equivalents at end of period	11,642	12,976
Non-cash investing activities:
Property, plant and equipment additions purchased at the period end, but not yet paid for	124,503	94,473
Non-cash utility property contributions	$ 25,980	$ 8,789