Retirement Benefits (Tables)

9 Months Ended

Sep. 30, 2021

Retirement Benefits [Abstract]

Calculation of Net Periodic Benefit Costs

A portion of the net periodic benefit cost for all plans is capitalized in the Consolidated Balance Sheets. The following table presents the components of Exelon's net periodic benefit costs, prior to capitalization, for the three and nine months ended September 30, 2021 and 2020.

	Pension Benefits				OPEB
	Three Months Ended September 30,				Three Months Ended September 30,
	2021		2020		2021		2020
Components of net periodic benefit cost:
Service cost	$	110	$	97	$	20	$	22
Interest cost	161		190		29		37
Expected return on assets	(335)		(317)		(40)		(41)
Amortization of:
Prior service cost (credit)	1		1		(8)		(30)
Actuarial loss	150		128		9		12
Settlement charges	12		8		—		—
Net periodic benefit cost	$	99	$	107	$	10	$	—

	Pension Benefits				OPEB
	Nine Months Ended September 30,				Nine Months Ended September 30,
	2021		2020		2021		2020
Components of net periodic benefit cost:
Service cost	$	330	$	290	$	60	$	67
Interest cost	481		569		86		114
Expected return on assets	(1,003)		(953)		(119)		(122)
Amortization of:
Prior service cost (credit)	3		3		(25)		(92)
Actuarial loss	449		384		27		36
Curtailment benefits	—		—		(1)		—
Settlement charges	16		14		—		—
Net periodic benefit cost	$	276	$	307	$	28	$	3

Allocated Portion of Pension and Postretirement Benefit Costs

The amounts below represent the Registrants' allocated pension and OPEB costs. For Exelon, the service cost component is included in Operating and maintenance expense and Property, plant, and equipment, net while the non-service cost components are included in Other, net and Regulatory assets. For Generation and the Utility Registrants, the service cost and non-service cost components are included in Operating and maintenance expense and Property, plant, and equipment, net in their consolidated financial statements.

	Three Months Ended September 30,				Nine Months Ended September 30,
Pension and OPEB Costs	2021		2020		2021		2020
Exelon	$	109	$	107	$	304	$	310
Generation	36		30		92		89
ComEd	32		29		97		85
PECO	2		1		5		4
BGE	16		16		47		47
PHI	12		17		36		52
Pepco	2		4		5		11
DPL	1		2		2		6
ACE	3		3		8		10

Defined Contribution Savings Plans

The Registrants participate in various 401(k) defined contribution savings plans that are sponsored by Exelon. The plans are qualified under applicable sections of the IRC and allow employees to contribute a portion of their pre-tax and/or after-tax income in accordance with specified guidelines. All Registrants match a percentage of the employee contributions up to certain limits. The following table presents the matching contributions to the savings plans for the three and nine months ended September 30, 2021 and 2020, respectively.

	Three Months Ended September 30,				Nine Months Ended September 30,
Savings Plans Matching Contributions	2021		2020		2021		2020
Exelon	$	38	$	37	$	107	$	104
Generation	14		14		40		41
ComEd	9		9		27		25
PECO	2		3		8		8
BGE	4		4		8		8
PHI	5		3		12		9
Pepco	1		1		3		3
DPL	1		1		3		2
ACE	1		—		2		1