Debt and Credit Agreements (Tables)

6 Months Ended

Jun. 30, 2019

Debt Disclosure [Abstract]

Commercial Paper Borrowings

The following table reflects the Registrants' commercial paper programs as of June 30, 2019 and December 31, 2018. Generation and PECO had no commercial paper borrowings as of both June 30, 2019 and December 31, 2018.

	Outstanding Commercial Paper as of				Average Interest Rate on Commercial Paper Borrowings as of
Commercial Paper Issuer	June 30, 2019		December 31, 2018		June 30, 2019		December 31, 2018
Exelon	$	559	$	89	2.60	%	2.15	%
ComEd	303		—		2.59	%	2.14	%
BGE	229		35		2.58	%	2.18	%
PHI	27		54		2.61	%	2.15	%
PEPCO	—		40		2.62	%	2.24	%
DPL	—		—		2.55	%	2.07	%
ACE	27		14		2.61	%	2.21	%

Schedule of Long-term Debt Instruments [Table Text Block]

During the six months ended June 30, 2019, the following long-term debt was issued:

Company	Type	Interest Rate		Maturity	Amount		Use of Proceeds
Generation	Energy Efficiency Project Financing	3.95	%	August 31, 2020	$	2	Funding to install energy conservation measures for the Fort Meade project.
Generation	Energy Efficiency Project Financing	3.46	%	May 1, 2020	$	39	Funding to install energy conservation measures for the Marine Corps. Logistics Project.
ComEd	First Mortgage Bonds, Series 126	4.00	%	March 1, 2049	$	400	Repay a portion of ComEd’s outstanding commercial paper obligations and fund other general corporate purposes.
Pepco	First Mortgage Bonds	3.45	%	June 13, 2029	$	150	Repay existing indebtedness and for general corporate purposes
Pepco	Unsecured Tax-Exempt Bonds	1.70	%	September 1, 2022	$	110	Repay existing indebtedness and for general corporate purposes
ACE	First Mortgage Bonds	3.50	%	May 21, 2029	$	100	Repay existing indebtedness and for general corporate purposes
ACE	First Mortgage Bonds	4.14	%	May 21, 2049	$	50	Repay existing indebtedness and for general corporate purposes