Borrowings and Other Financing Instruments Equity through DRIP and Benefits Program (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Forward Contract Indexed to Issuer's Equity [Line Items]
Proceeds from issuance of common stock			$ 83	$ 156
Issuances of common stock	$ 18	$ 14	113	185
Dividend Reinvestment Program
Forward Contract Indexed to Issuer's Equity [Line Items]
Proceeds from issuance of common stock			$ 78	$ 59