Borrowings and Other Financing Instruments Equity through DRIP and Benefits Program (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Forward Contract Indexed to Issuer's Equity [Line Items]
Proceeds from issuance of common stock			$ 75	$ 151
Issuances of common stock	$ 77	$ 159	95	171
Dividend Reinvestment Program
Forward Contract Indexed to Issuer's Equity [Line Items]
Proceeds from issuance of common stock			$ 61	$ 45