Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2022	Mar. 31, 2021
Income Statement [Abstract]
Operating Revenue	[1]	$ 849	$ 744
Operating Expenses:
Fuel used in electric generation	[1]	174	132
Purchased power	[1]	31	16
Gas purchased for resale		105	81
Other operations and maintenance		117	99
Other operations and maintenance - affiliated suppliers		43	53
Impairment of assets and other charges		0	60
Depreciation and amortization		125	121
Other taxes	[1]	73	65
Total operating expenses		668	627
Operating income		181	117
Other income, net		4	6
Interest charges, net of allowance for borrowed funds used during construction	[1]	52	55
Income before income tax expense		133	68
Income tax expense		26	13
Net Income and Other Comprehensive Income		107	55
Comprehensive Income Attributable to Noncontrolling Interest		4	4
Comprehensive Income Available to Common Shareholder		$ 103	$ 51

[1] See Note 12 for amounts attributable to affiliates.