Discontinued Operations (Details) - Cash Flow - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Business Dispositions [Line Items]
Depreciation, Amortization and Accretion, Net	$ 3,533	$ 7,573	$ 6,527
Asset Impairment Charges	48
Gain (Loss) on Sale of Assets and Asset Impairment Charges	8	201	24
Deferred Income Taxes and Tax Credits	255	18	309
Unrealized Gain (Loss) on Derivatives	53	568	268
Gain (Loss) on Investments	(205)	586	461
Other non-cash operating activities	(370)	200	(592)
Payments to Acquire Property, Plant, and Equipment	7,147	7,981	8,048
Collection of deferred purchase price	169	3,902	3,771
Increase (decrease) in capital expenditures not paid	36	16	194
Increase in Deferred Purchase Price	348	3,652	4,441
Increase (decrease) in PPE related to ARO update	332	642	850
Exelon Generation Co L L C [Member]
Business Dispositions [Line Items]
Depreciation, Amortization and Accretion, Net	207	4,540	3,636
Asset Impairment Charges	0	545	563
Gain (Loss) on Sale of Assets and Asset Impairment Charges	9	(201)	(11)
Deferred Income Taxes and Tax Credits	(143)	(224)	94
Unrealized Gain (Loss) on Derivatives	(59)	(568)	(270)
Gain (Loss) on Investments	205	(586)	(461)
Net unrealized losses (gains) on equity investments	16	160	(186)
Other non-cash operating activities	36	(946)	(659)
Payments to Acquire Property, Plant, and Equipment	(227)	(1,341)	(1,759)
Collection of deferred purchase price	169	3,902	3,771
Increase (decrease) in capital expenditures not paid	(128)	96	(88)
Increase in Deferred Purchase Price	348	3,652	4,441
Increase (decrease) in PPE related to ARO update	$ 335	$ 618	$ 850

The non cash impact of change in capital expenditures incurred but not yet paid.

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