Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Income Tax Contingency [Line Items]
Unrecognized Tax Benefits	$ 148	$ 148
Income Taxes Receivable, Noncurrent	50
Pepco Holdings LLC [Member]
Income Tax Contingency [Line Items]
Unrecognized Tax Benefits	59	59
Atlantic City Electric Company [Member]
Income Tax Contingency [Line Items]
Unrecognized Tax Benefits	$ 17	$ 17