Mergers, Acquisitions, and Dispositions PHI Impact on Exelon Consolidated (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Revenues	$ 8,769	$ 9,002	$ 25,149	$ 23,486
Net income	867	526	1,911	956
Pepco Holdings LLC [Member]
Segment Reporting Information [Line Items]
Revenues	1,347	1,437	3,679	2,656
Net income	$ 176	$ 169	$ 382	$ (92)

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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