CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Cash and cash equivalents	$ 90,000,000	$ 74,000,000
Accounts receivable	710,000,000	889,000,000
Allowance for credit losses	27,000,000	38,000,000
Accrued unbilled revenues, allowance for credit loss	2,000,000	4,000,000
Prepaid expenses and other current assets ($15 and $13 related to VIEs, respectively)	145,000,000	171,000,000
Regulatory assets	$ 2,513,000,000	$ 2,193,000,000
Preferred Stock [Abstract]
Cumulative preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Cumulative preferred stock, authorized (in shares)	20,000,000	20,000,000
Cumulative preferred stock, outstanding (in shares)	0	800,000
Cumulative preferred stock, aggregate liquidation preference	$ 0	$ 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)	631,225,829	629,535,631
Variable Interest Entity, Primary Beneficiary
Cash and cash equivalents	$ 90,000,000	$ 75,000,000
Accounts receivable	21,000,000	22,000,000
Accrued unbilled revenues, after allowance for credit losses, current	2,000,000	0
Prepaid expenses and other current assets ($15 and $13 related to VIEs, respectively)	15,000,000	13,000,000
Regulatory assets	$ 402,000,000	$ 229,000,000