Income Taxes (Tables)

6 Months Ended

Jun. 30, 2019

Income Tax Disclosure [Abstract]

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

The effective income tax rate from continuing operations varies from the U.S. Federal statutory rate principally due to the following:

	Three Months Ended June 30, 2019
	Exelon	Generation	ComEd	PECO	BGE	PHI	Pepco	DPL	ACE
U.S. Federal statutory rate	21.0%	21.0%	21.0%	21.0%	21.0%	21.0%	21.0%	21.0%	21.0%
Increase (decrease) due to:
State income taxes, net of Federal income tax benefit	5.4	5.5	8.2	(1.2)	6.5	4.8	2.0	7.0	7.0
Qualified NDT fund income	5.1	16.2	—	—	—	—	—	—	—
Amortization of investment tax credit, including deferred taxes on basis difference	(0.7)	(1.9)	(0.2)	—	(0.1)	(0.2)	(0.1)	(0.2)	(0.3)
Plant basis differences	(1.7)	—	(0.6)	(5.9)	(1.5)	(1.7)	(2.1)	(0.3)	(2.2)
Production tax credits and other credits	(0.9)	(2.8)	—	—	(0.1)	—	—	—	—
Noncontrolling interests	0.1	0.4	—	—	—	—	—	—	—
Excess deferred tax amortization	(7.8)	—	(9.0)	(2.7)	(7.9)	(19.4)	(18.3)	(15.7)	(23.1)
Other	1.9	0.2	0.4	0.1	1.7	0.9	0.5	—	(2.4)
Effective income tax rate	22.4%	38.6%	19.8%	11.3%	19.6%	5.4%	3.0%	11.8%	—%

	Three Months Ended June 30, 2018
	Exelon	Generation	ComEd	PECO	BGE	PHI	Pepco	DPL	ACE
U.S. Federal statutory rate	21.0%	21.0%	21.0%	21.0%	21.0%	21.0%	21.0%	21.0%	21.0%
Increase (decrease) due to:
State income taxes, net of Federal income tax benefit	3.4	4.3	8.1	(3.4)	6.5	6.2	4.7	6.5	7.6
Qualified NDT fund income	0.2	0.5	—	—	—	—	—	—	—
Amortization of investment tax credit, including deferred taxes on basis difference	(0.9)	(2.4)	(0.2)	(0.1)	(0.2)	(0.2)	(0.1)	(0.3)	(0.3)
Plant basis differences	(3.0)	—	(0.1)	(17.2)	(0.7)	(1.2)	(2.0)	—	(0.2)
Production tax credits and other credits	(1.7)	(4.9)	(0.1)	—	—	—	—	—	—
Noncontrolling interests	(1.5)	(4.5)	—	—	—	—	—	—	—
Excess deferred tax amortization	(5.2)	—	(7.6)	(0.3)	(7.2)	(11.3)	(11.7)	(11.2)	(8.8)
Tax Cuts and Jobs Act of 2017	(1.3)	(1.7)	(0.7)	—	0.1	0.8	—	—	—
Other	(0.2)	(1.3)	0.4	(1.1)	0.8	(0.1)	(0.4)	0.1	0.7
Effective income tax rate	10.8%	11.0%	20.8%	(1.1)%	20.3%	15.2%	11.5%	16.1%	20.0%

	Six Months Ended June 30, 2019
	Exelon	Generation	ComEd	PECO	BGE	PHI	Pepco	DPL	ACE
U.S. Federal statutory rate	21.0%	21.0%	21.0%	21.0%	21.0%	21.0%	21.0%	21.0%	21.0%
Increase (decrease) due to:
State income taxes, net of Federal income tax benefit	4.4	3.6	8.2	0.2	6.4	4.7	2.0	6.7	6.9
Qualified NDT fund income	6.5	14.7	—	—	—	—	—	—	—
Amortization of investment tax credit, including deferred taxes on basis difference	(0.6)	(1.1)	(0.2)	—	(0.1)	(0.2)	(0.1)	(0.2)	(0.3)
Plant basis differences	(1.5)	—	(0.6)	(6.4)	(1.0)	(1.7)	(2.0)	(0.6)	(2.2)
Production tax credits and other credits	(0.8)	(1.8)	—	—	—	—	—	—	—
Noncontrolling interests	(0.3)	(0.8)	—	—	—	—	—	—	—
Excess deferred tax amortization	(5.8)	—	(8.8)	(2.6)	(7.9)	(19.4)	(18.1)	(15.6)	(23.4)
Other	0.7	(0.4)	0.2	(0.1)	0.2	0.3	0.5	0.4	2.0
Effective income tax rate	23.6%	35.2%	19.8%	12.1%	18.6%	4.7%	3.3%	11.7%	4.0%

	Six Months Ended June 30, 2018
	Exelon	Generation	ComEd	PECO	BGE	PHI	Pepco	DPL	ACE
U.S. Federal statutory rate	21.0%	21.0%	21.0%	21.0%	21.0%	21.0%	21.0%	21.0%	21.0%
Increase (decrease) due to:
State income taxes, net of Federal income tax benefit	3.8	3.4	8.1	(3.6)	6.4	5.5	3.7	6.4	7.2
Qualified NDT fund income	(0.1)	(0.4)	—	—	—	—	—	—	—
Amortization of investment tax credit, including deferred taxes on basis difference	(1.1)	(3.3)	(0.2)	(0.1)	(0.1)	(0.2)	(0.1)	(0.3)	(0.3)
Plant basis differences	(2.8)	—	—	(15.6)	(0.7)	(1.8)	(2.5)	(0.7)	(1.3)
Production tax credits and other credits	(2.3)	(7.2)	(0.1)	—	—	—	—	—	—
Noncontrolling interests	(1.1)	(3.5)	—	—	—	—	—	—	—
Excess deferred tax amortization	(5.6)	—	(7.5)	(2.7)	(8.2)	(11.0)	(12.1)	(9.4)	(8.8)
Tax Cuts and Jobs Act of 2017	(0.6)	(0.9)	(0.3)	—	—	0.5	—	—	—
Other	(1.7)	(1.3)	0.1	(0.4)	0.2	(0.1)	(0.4)	0.4	(1.1)
Effective income tax rate	9.5%	7.8%	21.1%	(1.4)%	18.6%	13.9%	9.6%	17.4%	16.7%

Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]

The Registrants have the following unrecognized tax benefits as of June 30, 2019 and December 31, 2018:

	Exelon		Generation		ComEd		PECO		BGE		PHI		Pepco		DPL		ACE
June 30, 2019	$	448	$	411	$	—	$	—	$	—	$	45	$	—	$	—	$	14
December 31, 2018	$	477	$	408	$	2	$	—	$	—	$	45	$	—	$	—	$	14