Consolidated Statement of Changes in Shareholders Equity - USD ($) shares in Thousands, $ in Millions	Total	Common Stock [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss), net	Noncontrolling Interest [Member]	Commonwealth Edison Co [Member]	Commonwealth Edison Co [Member] Common Stock [Member]	Commonwealth Edison Co [Member] Retained Earnings [Member]	Commonwealth Edison Co [Member] Other Additional Capital [Member]	PECO Energy Co [Member]	PECO Energy Co [Member] Common Stock [Member]	PECO Energy Co [Member] Retained Earnings [Member]	Baltimore Gas and Electric Company [Member]	Baltimore Gas and Electric Company [Member] Common Stock [Member]	Baltimore Gas and Electric Company [Member] Retained Earnings [Member]	Pepco Holdings LLC [Member]	Pepco Holdings LLC [Member] Membership Interest [Member]	Pepco Holdings LLC [Member] Retained Earnings [Member]	Potomac Electric Power Company [Member]	Potomac Electric Power Company [Member] Common Stock [Member]	Potomac Electric Power Company [Member] Retained Earnings [Member]	Delmarva Power & Light Company [Member]	Delmarva Power & Light Company [Member] Common Stock [Member]	Delmarva Power & Light Company [Member] Retained Earnings [Member]	Atlantic City Electric Company [Member]	Atlantic City Electric Company [Member] Common Stock [Member]	Atlantic City Electric Company [Member] Retained Earnings [Member]
Beginning Balance (in shares) at Dec. 31, 2019	974,416
Beginning Balance at Dec. 31, 2019	$ 34,573	$ 19,274	$ (123)	$ 16,267	$ (3,194)	$ 2,349
Beginning Balance at Dec. 31, 2019																	$ 9,608	$ 9,618	$ (10)
Beginning Balance at Dec. 31, 2019							$ 10,677	$ 1,588	$ 1,517	$ 7,572	$ 4,178	$ 2,766	$ 1,412	$ 3,683	$ 1,907	$ 1,776				$ 2,907	$ 1,796	$ 1,111	$ 1,580	$ 977	$ 603	$ 1,283	$ 1,154	$ 129
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 1,954			1,963		(9)	438		438		447		447	349		349	495		495	266		266	125		125	112		112
Long-Term Incentive Plan Activity (shares)	1,570
Long-Term Incentive Plan Activity	$ 40	40
Employee stock purchase plan issuances, shares	1,480
Employee stock purchase plan issuances	$ 56	56
Sale of noncontrolling interests	3	3
Changes in equity of noncontrolling interests	(57)					(57)
Proceeds from Issuance of Common Stock	0
Acquisition of CENG noncontrolling interest	$ 0
Common Stock, Dividends, Per Share, Declared	$ 1.53
Common stock dividends	$ (1,495)			(1,495)			(499)		(499)		(340)		(340)	(246)		(246)				(232)		(232)	(141)		(141)	(114)		(114)
Other Comprehensive Income (Loss), Net of Tax	$ (206)				(206)
Distributions to member																	(553)		(553)
Contributions from parent							713			713	248	248		411	411		494	494		262	262		112	112		117	117
Ending Balance (in shares) at Dec. 31, 2020	977,466
Ending Balance at Dec. 31, 2020	$ 34,868	19,373	(123)	16,735	(3,400)	2,283
Ending Balance at Dec. 31, 2020							11,329	1,588	1,456	8,285	4,533	3,014	1,519	4,197	2,318	1,879				3,203	2,058	1,145	1,676	1,089	587	1,398	1,271	127
Ending Balance at Dec. 31, 2020																	10,044	10,112	(68)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 1,829			1,706		123	742		742		504		504	408		408	561		561	296		296	128		128	146		146
Long-Term Incentive Plan Activity (shares)	1,734
Long-Term Incentive Plan Activity	$ 69	69
Employee stock purchase plan issuances, shares	2,091
Employee stock purchase plan issuances	$ 90	90
Changes in equity of noncontrolling interests	(37)					(37)
Proceeds from Issuance of Common Stock	0
Acquisition of CENG noncontrolling interest	(885)	1,080				(1,965)
Deferred Tax Liability Adjustment - Noncontrolling Interest	$ (290)	(290)
Common Stock, Dividends, Per Share, Declared	$ 1.53
Common stock dividends	$ (1,499)			(1,499)			(507)		(507)		(339)		(339)	(292)		(292)				(268)		(268)	(147)		(147)	(288)		(288)
Payments to Noncontrolling Interests	0	2				(2)
Other Comprehensive Income (Loss), Net of Tax	$ 650				650
Distributions to member																	(703)		(703)
Contributions from parent							791			791	414	414		257	257		683	683		244	244		120	120		319	319
Ending Balance (in shares) at Dec. 31, 2021	981,291
Ending Balance at Dec. 31, 2021	$ 34,795	20,324	(123)	16,942	(2,750)	402
Ending Balance at Dec. 31, 2021	34,393						12,355	1,588	1,691	9,076	5,112	3,428	1,684	4,570	2,575	1,995				3,475	2,302	1,173	1,777	1,209	568	1,575	1,590	(15)
Ending Balance at Dec. 31, 2021																	10,585	10,795	(210)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 2,171			2,170		1	917		917		576		576	380		380	608		608	305		305	169		169	148		148
Long-Term Incentive Plan Activity (shares)	561
Long-Term Incentive Plan Activity	$ 1	1
Employee stock purchase plan issuances, shares	983
Employee stock purchase plan issuances	$ 41	41
Changes in equity of noncontrolling interests	(7)					(7)
Distribution of Constellation	(11,573)	(21)		(13,179)	2,023	(396)
Proceeds from Issuance of Common Stock	$ 563	563
Stock Issued During Period, Shares, New Issues	12,995
Acquisition of CENG noncontrolling interest	$ 0
Common Stock, Dividends, Per Share, Declared	$ 1.35
Common stock dividends	$ (1,336)			(1,336)			(578)		(578)		(399)		(399)	(300)		(300)				(463)		(463)	(143)		(143)	(145)		(145)
Other Comprehensive Income (Loss), Net of Tax	$ 89				89
Distributions to member																	(750)		(750)
Contributions from parent							670			670	274	274		286	286		787	787		465	465		147	147		175	175
Ending Balance (in shares) at Dec. 31, 2022	995,830
Ending Balance at Dec. 31, 2022	$ 24,744	$ 20,908	$ (123)	$ 4,597	$ (638)	$ 0
Ending Balance at Dec. 31, 2022	$ 24,744						$ 13,364	$ 1,588	$ 2,030	$ 9,746	$ 5,563	$ 3,702	$ 1,861	$ 4,936	$ 2,861	$ 2,075				$ 3,782	$ 2,767	$ 1,015	$ 1,950	$ 1,356	$ 594	$ 1,753	$ 1,765	$ (12)
Ending Balance at Dec. 31, 2022																	$ 11,230	$ 11,582	$ (352)