Unaudited Condensed Consolidated Statements Of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Costs and Expenses	$ 302,280	$ 274,101	$ 874,291	$ 810,508
REVENUES	380,837	356,088	1,073,625	1,024,973
Cost of Revenue [Abstract]
Fuel Costs	68,857	73,901	206,428	186,040
Cost of Goods and Services Sold	40,443	26,987	106,774	105,536
OPERATING EXPENSES:
Utilities Operating Expense, Maintenance and Operations	117,045	100,455	337,375	300,703
Depreciation and amortization	64,797	62,359	190,880	184,166
Taxes other than income taxes	11,138	10,399	32,834	34,063
Operating Income (Loss)	78,557	81,987	199,334	214,465
Allowance for equity funds used during construction	1,428	1,099	4,133	3,116
Interest Expense	31,544	32,741	93,810	96,757
Other Nonoperating Income (Expense)	4,572	935	13,890	2,914
Nonoperating Income (Expense)	(25,544)	(30,707)	(75,787)	(93,142)
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	53,013	51,280	123,547	121,323
Income Tax Expense (Benefit)	10,966	10,981	25,506	25,918
Net income	42,047	40,299	98,041	95,405
Less: Dividends on preferred stock	803	803	2,410	2,410
Net Income (Loss) Available to Common Stockholders, Basic	41,244	39,496	95,631	92,995
Gain (Loss) on Extinguishment of Debt	0	0	0	(2,415)
OPERATING INCOME	78,557	81,987	199,334	214,465
OTHER INCOME / (EXPENSE), NET:
Allowance for equity funds used during construction	1,428	1,099	4,133	3,116
Interest Expense	(31,544)	(32,741)	(93,810)	(96,757)
Other Nonoperating Income (Expense)	4,572	935	13,890	2,914
Total other expense, net	(25,544)	(30,707)	(75,787)	(93,142)
EARNINGS FROM OPERATIONS BEFORE INCOME TAX
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	53,013	51,280	123,547	121,323
Income Tax Expense (Benefit)	10,966	10,981	25,506	25,918
NET INCOME	42,047	40,299	98,041	95,405
Less: Dividends on preferred stock	803	803	2,410	2,410
NET INCOME APPLICABLE TO COMMON STOCK	$ 41,244	$ 39,496	$ 95,631	$ 92,995