Discontinued Operations (Details) - Income Statement - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Business Dispositions [Line Items]
Operating and maintenance	$ 4,673	$ 4,547	$ 4,641
Depreciation and Amortization	3,325	3,033	2,891
Taxes, Miscellaneous	1,390	1,291	1,232
Costs and Expenses	15,761	15,256	14,485
Other Nonoperating Income (Expense)	535	261	208
Nonoperating Income (Expense)	(912)	(1,028)	(1,099)
Income taxes	349	38	(7)
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	117	213	855
Net income (loss) attributable to noncontrolling interests	1	123	(9)
Net Income (Loss) from Discontinued Operations Available to Common Shareholders, Basic	116	90	864
Total transaction costs relating to the Separation	12
Total transaction and transition costs incurred related to the Separation	52	43	0
Exelon Generation Co L L C [Member]
Business Dispositions [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	1,855	18,466	16,399
Operating revenues from affiliates	161	1,189	1,206
Disposal Group, Including Discontinued Operation, Revenue	2,016	19,655	17,605
Purchased power and/or fuel	1,138	12,163	9,585
Operating and maintenance	371	4,174	4,794
Depreciation and Amortization	94	3,003	2,123
Taxes, Miscellaneous	44	475	482
Costs and Expenses	1,647	19,815	16,984
Gain (Loss) on Disposition of Assets	10	201	11
Disposal Group, Including Discontinued Operation, Operating Income (Loss)	379	41	632
Disposal Group, Including Discontinued Operation, Interest Expense	(20)	(282)	(328)
Other Nonoperating Income (Expense)	(281)	795	937
Nonoperating Income (Expense)	(301)	513	609
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax	78	554	1,241
Income taxes	(40)	332	380
Equity in losses of unconsolidated affiliates	(1)	(9)	(6)
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	117	213	855
Net income (loss) attributable to noncontrolling interests	1	123	(9)
Net Income (Loss) from Discontinued Operations Available to Common Shareholders, Basic	$ 116	$ 90	$ 864