Income Taxes (Tables)

3 Months Ended

Mar. 31, 2017

Income Tax Disclosure [Abstract]

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

	Three Months Ended March 31, 2017
									Successor
	Exelon	Generation	ComEd	PECO	BGE	Pepco	DPL	ACE	PHI
U.S. Federal statutory rate	35.0%	35.0%	35.0%	35.0%	35.0%	35.0%	35.0%	35.0%	35.0%
Increase (decrease) due to:
State income taxes, net of Federal income tax benefit	0.9	1.0	4.9	0.1	5.2	4.6	5.3	5.6	4.9
Qualified nuclear decommissioning trust fund income	3.4	7.6	—	—	—	—	—	—	—
Amortization of investment tax credit, including deferred taxes on basis difference	(0.4)	(0.7)	(0.2)	(0.1)	(0.1)	(0.1)	(0.3)	(0.4)	(0.2)
Plant basis differences	(2.4)	—	(0.2)	(13.2)	(0.9)	(5.8)	(1.9)	(3.4)	(3.8)
Production tax credits and other credits	(0.6)	(1.4)	—	—	—	—	—	—	—
Noncontrolling interests	(0.1)	(0.3)	—	—	—	—	—	—	—
Merger expenses(a)	(11.4)	(3.3)	—	—	—	(34.2)	(21.9)	(167.1)	(42.4)
Fitzpatrick bargain purchase gain	(6.6)	(14.5)	—	—	—	—	—	—	—
Other	—	(0.1)	—	0.3	(0.2)	0.5	—	(3.0)	(0.4)
Effective income tax rate	17.8%	23.3%	39.5%	22.1%	39.0%	0.0%	16.2%	(133.3)%	(6.9)%

									Successor	Predecessor
	Three Months Ended March 31, 2016								March 24, 2016 to March 31, 2016	January 1, 2016 to March 23, 2016
	Exelon	Generation	ComEd	PECO	BGE	Pepco(b)	DPL(b)	ACE(b)	PHI(b)	PHI
U.S. Federal statutory rate	35.0%	35.0%	35.0%	35.0%	35.0%	35.0%	35.0%	35.0%	35.0%	35.0%
Increase (decrease) due to:
State income taxes, net of Federal income tax benefit (c)	(1.1)	3.7	5.1	1.0	5.2	(2.5)	(2.7)	5.9	5.4	11.9
Qualified nuclear decommissioning trust fund income	5.6	4.2	—	—	—	—	—	—	—	—
Amortization of investment tax credit, including deferred taxes on basis difference	(1.6)	(1.0)	(0.3)	(0.1)	(0.1)	—	0.1	0.2	—	(0.9)
Plant basis differences	(5.5)	—	(0.1)	(9.3)	(0.6)	2.8	0.7	0.6	—	(13.5)
Production tax credits and other credits	(5.1)	(3.9)	—	—	—	—	—	—	—	—
Noncontrolling interests	0.5	0.3	—	—	—	—	—	—	—	—
Merger expenses	33.6	—	—	—	—	(16.5)	(22.1)	(17.0)	(15.1)	11.1
Other	(2.0)	(1.6)	0.4	(0.9)	—	—	0.1	0.1	0.2	3.6
Effective income tax rate	59.4%	36.7%	40.1%	25.7%	39.5%	18.8%	11.1%	24.8%	25.5%	47.2%