CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
OPERATING ACTIVITIES:
Net Income	$ 116,264	$ 135,504
Items not affecting cash:
Depreciation and depletion	145,705	140,896
Amortization of debt issuance costs, discount and deferred hedge gain	4,044	3,951
Stock-based compensation costs	4,324	5,850
Equity portion of allowance for funds used during construction	(9,983)	(7,829)
Loss on disposition of assets	524	6,536
Deferred income taxes	(12,127)	(681)
Changes in current assets and liabilities:
Accounts receivable	49,522	28,901
Inventories	(48,639)	(23,400)
Other current assets	(5,139)	(8,442)
Accounts payable	36,064	(12,472)
Accrued expenses and other	67,636	85,015
Regulatory assets	(20,788)	(67,672)
Regulatory liabilities	(6,398)	(32,941)
Other noncurrent assets	8,968	610
Other noncurrent liabilities	(20,707)	(32,216)
Cash Provided by Operating Activities	309,270	221,610
INVESTING ACTIVITIES:
Property, plant, and equipment additions	(386,339)	(311,160)
Investment in equity securities	(914)	(655)
Cash Used in Investing Activities	(387,253)	(311,815)
FINANCING ACTIVITIES:
Proceeds from Issuance of Common Stock	179,903	121,066
Dividends on common stock	(102,980)	(95,148)
Issuance of long-term debt, net	0	99,915
Line of credit borrowings, net	12,000	73,000
Payment for Debt Extinguishment or Debt Prepayment Cost	0	(955)
Repayments of short-term borrowings	0	(100,000)
Proceeds from (Payments for) Other Financing Activities	(977)	(550)
Cash Provided by Financing Activities	87,946	97,328
Increase in Cash, Cash Equivalents, and Restricted Cash	9,963	7,123
Cash, Cash Equivalents, and Restricted Cash, beginning of period	18,762	17,096
Cash, Cash Equivalents, and Restricted Cash, end of period	28,725	24,219
Cash paid during the period for:
Income taxes	9,060	3,630
Interest	60,610	57,473
Significant non-cash transactions:
Capital expenditures included in accounts payable	$ 26,184	$ 23,500