Condensed Statements of Consolidated Changes in Equity (Unaudited) - CERC - USD ($) $ in Millions	Total	Common Stock	Additional Paid-in-Capital	Retained Earnings	Accumulated Other Comprehensive Loss	CERC	CERC Common Stock	CERC Additional Paid-in-Capital	CERC Retained Earnings	CERC Accumulated Other Comprehensive Loss
Balance, beginning of period (in shares) at Dec. 31, 2022		630,000,000					1,000
Balance, beginning of period at Dec. 31, 2022		$ 6	$ 8,568	$ 709	$ (31)		$ 0	$ 3,729	$ 1,618	$ 16
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Contribution from parent								500
Net income	$ 443			443		$ 255			255
Dividend to parent									(311)
Other comprehensive loss					(1)					(1)
Balance, end of period (in shares) at Jun. 30, 2023		631,000,000					1,000
Balance, end of period at Jun. 30, 2023	10,366	$ 6	8,570	1,032	(32)	5,806	$ 0	4,229	1,562	15
Balance, beginning of period (in shares) at Mar. 31, 2023		631,000,000					1,000
Balance, beginning of period at Mar. 31, 2023		$ 6	8,558	1,034	(32)		$ 0	3,729	1,626	15
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Contribution from parent								500
Net income	118			118		43			43
Dividend to parent									(107)
Other comprehensive loss					0					0
Balance, end of period (in shares) at Jun. 30, 2023		631,000,000					1,000
Balance, end of period at Jun. 30, 2023	$ 10,366	$ 6	8,570	1,032	(32)	5,806	$ 0	4,229	1,562	15
Balance, beginning of period (in shares) at Dec. 31, 2023	631,225,829	631,000,000					1,000
Balance, beginning of period at Dec. 31, 2023	$ 9,667	$ 6	8,604	1,092	(35)	5,879	$ 0	4,229	1,634	16
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Contribution from parent								290
Net income	$ 578			578		311			311
Dividend to parent									(246)
Other comprehensive loss					5					(1)
Balance, end of period (in shares) at Jun. 30, 2024	641,953,090	642,000,000					1,000
Balance, end of period at Jun. 30, 2024	$ 10,354	$ 6	8,836	1,542	(30)	6,233	$ 0	4,519	1,699	15
Balance, beginning of period (in shares) at Mar. 31, 2024		633,000,000					1,000
Balance, beginning of period at Mar. 31, 2024		$ 6	8,583	1,442	(33)		$ 0	4,229	1,783	15
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Contribution from parent								290
Net income	$ 228			228		47			47
Dividend to parent									(131)
Other comprehensive loss					3					0
Balance, end of period (in shares) at Jun. 30, 2024	641,953,090	642,000,000					1,000
Balance, end of period at Jun. 30, 2024	$ 10,354	$ 6	$ 8,836	$ 1,542	$ (30)	$ 6,233	$ 0	$ 4,519	$ 1,699	$ 15