Discontinued Operations and Disposal Groups (Details) - Cash Flows - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Discontinued Operations - Income Statement
Depreciation, Amortization and Accretion, Net	$ 1,024	$ 2,104
Gain (Loss) on Sale of Assets and Asset Impairment Charges	(10)	(71)
Deferred income taxes and amortization of investment tax credits	110	(142)
Net fair value changes related to derivatives	(59)	(178)
Net realized and unrealized (gains) losses on NDT funds	205	(118)
Net unrealized (gains) losses on equity investments	16	23
Other non-cash operating activities	(232)	170
Payments to Acquire Property, Plant, and Equipment	(1,922)	(2,140)
Collection of deferred purchase price	169	1,574
Decrease in capital expenditures not paid	(322)	(324)
Increase in deferred purchase price	348	1,339
Increase in PPE related to ARO update	(335)	2
Exelon Generation Co L L C [Member]
Discontinued Operations - Income Statement
Depreciation, Amortization and Accretion, Net	207	1,346
Gain (Loss) on Sale of Assets and Asset Impairment Charges	9	(71)
Deferred income taxes and amortization of investment tax credits	(143)	(234)
Net fair value changes related to derivatives	(59)	(178)
Net realized and unrealized (gains) losses on NDT funds	205	(118)
Net unrealized (gains) losses on equity investments	16	23
Other non-cash operating activities	36	(332)
Payments to Acquire Property, Plant, and Equipment	(227)	(394)
Collection of deferred purchase price	169	1,574
Decrease in capital expenditures not paid	(128)	(37)
Increase in deferred purchase price	348	1,339
Increase in PPE related to ARO update	$ 335	$ 0

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

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Amount of gain (loss) from the difference between the sale price or salvage price and the book value of an asset that was sold or retired, and gain (loss) from the write down of assets from their carrying value to fair value.

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