Discontinued Operations and Disposal Groups (Details) - Income Statement - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Discontinued Operations - Income Statement
Cost, Depreciation and Amortization	$ 866	$ 830	$ 1,727	$ 1,647
Taxes, Miscellaneous	324	330	679	684
Costs and Expenses	4,114	3,543	8,571	7,971
Other, net	139	175	249	313
Nonoperating Income (Expense)	(288)	(183)	(591)	(384)
Income taxes	73	46	206	263
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	0	0	0	117
Net income (loss) attributable to noncontrolling interests	0	0	0	1
Net Income (Loss) from Discontinued Operations Available to Common Shareholders, Basic	0	0	0	116
Total transaction and transition costs incurred related to the Separation				52
Nonrelated Party
Discontinued Operations - Income Statement
Operating and maintenance	1,197	1,109	2,347	2,288
Exelon Generation Co L L C [Member]
Discontinued Operations - Income Statement
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
Costs and 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)
Nonoperating Income (Expense)	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)
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	0	0	0	117
Net income (loss) attributable to noncontrolling interests	0	0	0	1
Net Income (Loss) from Discontinued Operations Available to Common Shareholders, Basic	0	0	0	116
Exelon Generation Co L L C [Member] | Nonrelated Party
Discontinued Operations - Income Statement
Revenue from Contract with Customer, Including Assessed Tax	0	0	0	1,855
Exelon Generation Co L L C [Member] | Related Party
Discontinued Operations - Income Statement
Revenue from Contract with Customer, Including Assessed Tax	$ 0	$ 0	$ 0	$ 161