Revenue Recognition - Schedule of Bad Debt Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Bad debt expense	$ 20	$ 12	$ 24
Bad debt expense deferred as regulatory asset	0	16	17
Houston Electric
Bad debt expense	0	0	0
Bad debt expense deferred as regulatory asset	0	8	0
CERC Corp
Bad debt expense	17	10	21
Bad debt expense deferred as regulatory asset	$ 0	$ 8	$ 16