Lessor - Components of Operating Lease Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Schedule of Operating Lease, Lease Income [Line Items]
Operating Lease Income	$ 4	$ 5	$ 5
Variable Lease Income	1	1	1
Commonwealth Edison Co [Member]
Schedule of Operating Lease, Lease Income [Line Items]
Operating Lease Income	0	0	0
Variable Lease Income	0	0	0
PECO Energy Co [Member]
Schedule of Operating Lease, Lease Income [Line Items]
Operating Lease Income	0	0	0
Variable Lease Income	0	0	0
Baltimore Gas and Electric Company [Member]
Schedule of Operating Lease, Lease Income [Line Items]
Operating Lease Income	0	0	0
Variable Lease Income	0	0	0
Pepco Holdings LLC [Member]
Schedule of Operating Lease, Lease Income [Line Items]
Operating Lease Income	4	4	3
Variable Lease Income	1	1	1
Potomac Electric Power Company [Member]
Schedule of Operating Lease, Lease Income [Line Items]
Operating Lease Income	0	0	0
Variable Lease Income	0	0	0
Delmarva Power & Light Company [Member]
Schedule of Operating Lease, Lease Income [Line Items]
Operating Lease Income	3	3	3
Variable Lease Income	$ 1	$ 1	$ 1