Unaudited Condensed Consolidated Statements Of Operations - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Costs and Expenses	$ 289,477	$ 308,767	$ 586,998	$ 603,597
REVENUES	340,869	359,678	723,178	714,182
Cost of Revenue [Abstract]
Fuel Costs	72,217	93,979	161,016	161,836
Cost of Goods and Services Sold	36,719	36,119	69,643	92,313
OPERATING EXPENSES:
Utilities Operating Expense, Maintenance and Operations	113,661	103,900	215,807	205,581
Depreciation and amortization	59,897	59,286	119,566	114,612
Taxes other than income taxes	6,983	15,483	20,966	29,255
OPERATING INCOME	51,392	50,911	136,180	110,585
OTHER INCOME / (EXPENSE), NET:
Allowance for equity funds used during construction	817	2,278	1,728	7,380
Interest Expense	(30,291)	(23,780)	(60,773)	(47,548)
Other Nonoperating Income (Expense)	(2,045)	(232)	(5,273)	(1,892)
Total other income and (expense), net	(31,519)	(21,734)	(64,318)	(42,060)
EARNINGS FROM OPERATIONS BEFORE INCOME TAX
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	19,873	29,177	71,862	68,525
Income Tax Expense (Benefit)	4,960	5,931	15,164	12,976
NET INCOME	14,913	23,246	56,698	55,549
Less: Dividends on preferred stock	804	804	1,607	1,607
NET INCOME APPLICABLE TO COMMON STOCK	14,109	22,442	55,091	53,942
Electricity [Member]
REVENUES	$ 340,869	$ 359,678	$ 723,178	$ 714,182