The net gains or losses recognized for each transaction with the acquiree that was recognized separately from the acquisition of assets and assumptions of liabilities in the business combination.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(3)
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- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 10.C)
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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
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No definition available.

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Early Plant Retirements Early Plant Retirements - Narrative (Details) - USD ($) $ in Millions		12 Months Ended
	Oct. 01, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Payments to Acquire Businesses, Gross		$ 154	$ 208	$ 6,923
Exelon Generation Co L L C [Member]
Property, Plant and Equipment [Line Items]
Payments to Acquire Businesses, Gross		$ 154	$ 208	$ 293
Exelon Generation Co L L C [Member] \| Nuclear Plant [Member]
Property, Plant and Equipment [Line Items]
Ownership interest		42.59%
Everett Marine Terminal [Member] \| Exelon Generation Co L L C [Member]
Property, Plant and Equipment [Line Items]
Payments to Acquire Businesses, Gross	$ 81
Business Combination, Separately Recognized Transactions, Net Gains and Losses	$ 75