CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Operating revenues
Electric, non-affiliates	$ 815	$ 800	$ 733
Electric, affiliates	204	202	189
Natural gas	157	198	182
Other	1	1	1
Total operating revenues	1,177	1,201	1,105
Operating expenses
Electric fuel and purchased power, non-affiliates	14	17	20
Purchased power, affiliates	408	446	408
Cost of natural gas sold and transported	80	116	117
Operating and maintenance expenses	239	223	198
Conservation program expenses	13	13	13
Depreciation and amortization	170	158	147
Taxes (other than income taxes)	34	31	28
Workforce Reduction Expense	5	0	0
Total operating expenses	963	1,004	931
Operating income	214	197	174
Other Income and Expenses [Abstract]
Other income (expense), net	2	(2)	(1)
Allowance for funds used during construction — equity	10	7	5
Interest charges and financing costs
Interest charges — includes other financing costs of $2, $1 and $1, respectively	54	45	42
Allowance for funds used during construction — debt	(4)	(3)	(2)
Total interest charges and financing costs	50	42	40
Income before income taxes	176	160	138
Income tax expense	40	35	30
Net income	$ 136	$ 125	$ 108