Discontinued Operations and Disposal Groups (Details) - Narrative - USD ($) $ in Millions	3 Months Ended		5 Months Ended	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022	Feb. 01, 2022
Discontinued Operations - Income Statement
Discontinued Operation, Intra-Entity Amounts, Discontinued Operation after Disposal, Expense	$ 44	$ 69	$ 125	$ 94
Nonoperating Income (Expense)	(288)	(183)		(591)	$ (384)
Net Income (Loss) from Discontinued Operations Available to Common Shareholders, Basic	0	0		0	116
Income taxes	73	46		206	263
Other, net	139	175		249	313
Net income (loss) attributable to noncontrolling interests	0	0		0	1
Taxes, Miscellaneous	324	330		679	684
Revenues	4,818	4,239		10,380	9,566
Cost, Depreciation and Amortization	866	830		1,727	1,647
Costs and Expenses	4,114	3,543		8,571	7,971
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	0	0		0	117
Total Liabilities	73,001			73,001		$ 70,605
Assets	98,080			98,080		95,349
Decrease in capital expenditures not paid				(164)	(276)
Collection of deferred purchase price				0	169
Other non-cash operating activities				222	(276)
Increase in PPE related to ARO update				0	(335)
Unrealized Gain (Loss) on Derivatives				(4)	59
Capital expenditures				3,685	3,507
Depreciation, Amortization and Accretion, Net				1,727	1,854
Gain (Loss) on Investments				0	(205)
Deferred income taxes and amortization of investment tax credits				94	143
Increase in deferred purchase price				0	348
Gain (Loss) on Sale of Assets and Asset Impairment Charges				0	8
Unrealized loss on equity investments				0	(16)
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
Discontinued Operation, Intra-Entity Amounts, Discontinued Operation after Disposal, Expense	3	11	$ 20	9
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax	0	0		0	78
Purchased power and/or fuel	0	0		0	1,138
Gain (Loss) on Disposition of Assets	0	0		0	10
Disposal Group, Including Discontinued Operation, Interest Expense	0	0		0	20
Operating and maintenance	0	0		0	371
Nonoperating Income (Expense)	0	0		0	(301)
Net Income (Loss) from Discontinued Operations Available to Common Shareholders, Basic	0	0		0	116
Income taxes	0	0		0	(40)
Other, net	0	0		0	(281)
Net income (loss) attributable to noncontrolling interests	0	0		0	1
Taxes, Miscellaneous	0	0		0	44
Income (Loss) from Equity Method Investments	0	0		0	(1)
Cost, Depreciation and Amortization	0	0		0	94
Disposal Group, Including Discontinued Operation, Operating Income (Loss)	0	0		0	379
Costs and Expenses	0	0		0	1,647
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	0	0		0	117
Disposal Group, Including Discontinued Operation, Revenue	0	0		0	2,016
Total Liabilities	0			0		0
Assets	0			0		$ 0
Net assets							$ (11,573)
Decrease in capital expenditures not paid				0	(128)
Collection of deferred purchase price				0	169
Other non-cash operating activities				0	36
Increase in PPE related to ARO update				0	335
Unrealized Gain (Loss) on Derivatives				0	59
Capital expenditures				0	227
Depreciation, Amortization and Accretion, Net				0	207
Gain (Loss) on Investments				0	(205)
Deferred income taxes and amortization of investment tax credits				0	(143)
Increase in deferred purchase price				0	348
Gain (Loss) on Sale of Assets and Asset Impairment Charges				0	(9)
Unrealized loss on equity investments				0	(16)
Revenues from Related Parties	0	0		0
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
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