Discontinued Operations and Disposal Groups (Details) - Income Statement - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Discontinued Operations - Income Statement
Operating and maintenance	$ 1,187	$ 1,148	$ 3,535	$ 3,436
Cost, Depreciation and Amortization	890	825	2,616	2,472
Taxes, Miscellaneous	383	377	1,063	1,061
Total operating expenses	4,857	3,834	13,429	11,804
Other, net	81	122	331	435
Total other income and (deductions)	(356)	(243)	(946)	(628)
Income taxes	67	92	274	356
Net income from discontinued operations after income taxes (Note 2)	0	0	0	117
Net income attributable to noncontrolling interests	0	0	0	1
Net income from discontinued operations	0	0	0	116
Total transaction and transition costs incurred related to the Separation				52
Exelon Generation Co L L C
Discontinued Operations - Income Statement
Electric operating revenues	0	0	0	1,855
Disposal Group, Including Discontinued Operation, Revenue	0	0	0	2,016
Purchased power and/or fuel	0	0	0	1,138
Operating and maintenance	0	0	0	371
Cost, Depreciation and Amortization	0	0	0	94
Taxes, Miscellaneous	0	0	0	44
Total operating expenses	0	0	0	1,647
Gain (Loss) on Disposition of Assets	0	0	0	10
Disposal Group, Including Discontinued Operation, Operating Income (Loss)	0	0	0	379
Disposal Group, Including Discontinued Operation, Interest Expense	0	0	0	(20)
Other, net	0	0	0	(281)
Total other income and (deductions)	0	0	0	(301)
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax	0	0	0	78
Income taxes	0	0	0	(40)
Income (Loss) from Equity Method Investments	0	0	0	(1)
Net income from discontinued operations after income taxes (Note 2)	0	0	0	117
Net income attributable to noncontrolling interests	0	0	0	1
Net income from discontinued operations	0	0	0	116
Exelon Generation Co L L C | Related Party
Discontinued Operations - Income Statement
Operating revenues from affiliates	$ 0	$ 0	$ 0	$ 161