Severance Severance - Narrative (Details) - Cost Management Project [Member]	1 Months Ended
	Aug. 31, 2015
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Number of Positions Eliminated	500
Corporate, Non-Segment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Number of Positions Eliminated	250
Exelon Generation Co L L C [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Number of Positions Eliminated	250