Mergers, Acquisitions, and Dispositions PHI Impact on Exelon Consolidated (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Segment Reporting Information [Line Items]
Revenues	$ 7,623	$ 6,910	$ 16,381	$ 14,485
Net income	64	306	1,046	430
Pepco Holdings LLC [Member]
Segment Reporting Information [Line Items]
Revenues	1,113	1,112	2,332	1,219
Net income	$ 61	$ 52	$ 202	$ (262)

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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