CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating revenues
Electric, non-affiliates	$ 733	$ 687	$ 668
Electric, affiliates	189	168	177
Natural gas	182	119	136
Other	1	0	0
Total operating revenues	1,105	974	981
Operating expenses
Electric fuel and purchased power, non-affiliates	20	13	11
Purchased power, affiliates	408	379	394
Cost of natural gas sold and transported	117	53	65
Operating and maintenance expenses	198	191	201
Conservation program expenses	13	13	12
Depreciation and amortization	147	156	138
Taxes (other than income taxes)	28	28	29
Total operating expenses	931	833	850
Operating income	174	141	131
Other Income and Expenses [Abstract]
Other expense, net	(1)	(8)	(1)
Allowance for funds used during construction — equity	5	5	3
Interest charges and financing costs
Interest charges — includes other financing costs of $1, $1 and $1, respectively	42	40	39
Allowance for funds used during construction — debt	(2)	(2)	(1)
Total interest charges and financing costs	40	38	38
Income before income taxes	138	100	95
Income tax expense (benefit)	30	(7)	16
Net income	$ 108	$ 107	$ 79