Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Cash and cash equivalents	$ 114	$ 74
Accounts receivable, less allowance for credit losses	874	889
Allowance for credit losses	43	38
Accrued unbilled revenues, allowance for credit losses	3	4
Prepaid expenses and other current assets	147	171
Regulatory assets	$ 2,499	$ 2,193
Preferred Stock [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized (in shares)	20,000,000	20,000,000
Preferred stock, outstanding (in shares)	800,000	800,000
Preferred stock aggregate liquidation preference	$ 800	$ 800
Common Stock [Abstract]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, outstanding (in shares)	631,018,976	629,535,631
Variable Interest Entity, Primary Beneficiary
Cash and cash equivalents	$ 110	$ 75
Accounts receivable, less allowance for credit losses	18	22
Prepaid expenses and other current assets	12	13
Regulatory assets	$ 199	$ 229