Intangible Assets - Schedule of Other Intangible Assets (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets and Liabilities [Line Items]
Finite-Lived Intangible Liabilities, Gross	$ (1,434)	$ (1,434)
Finite-Lived Intangible Liabilities, Accumulated Amortization	1,410	1,409
Finite-Lived Intangible Liabilities, Net	(24)	(25)
Unamortized Energy Contracts
Finite-Lived Intangible Assets and Liabilities [Line Items]
Finite-Lived Intangible Liabilities, Gross	(1,515)	(1,515)
Finite-Lived Intangible Liabilities, Accumulated Amortization	1,480	1,470
Finite-Lived Intangible Liabilities, Net	(35)	(45)
Long-term software licensing agreement
Finite-Lived Intangible Assets and Liabilities [Line Items]
Gross	81	81
Accumulated Amortization	(70)	(61)
Net	11	20
Pepco Holdings LLC | Unamortized Energy Contracts
Finite-Lived Intangible Assets and Liabilities [Line Items]
Finite-Lived Intangible Liabilities, Gross	(1,515)	(1,515)
Finite-Lived Intangible Liabilities, Accumulated Amortization	1,480	1,470
Finite-Lived Intangible Liabilities, Net	$ (35)	$ (45)