Commitments and Contingencies - Schedule of PHI Merger Commitments (Details) $ in Millions	Dec. 31, 2023 USD ($)
PHI Merger Commitments [Line Items]
Other Commitment	$ 638
PEPCO Holdings Inc
PHI Merger Commitments [Line Items]
Other Commitment	513
Pepco Holdings LLC
PHI Merger Commitments [Line Items]
Other Commitment	123
Pepco Holdings LLC | PEPCO Holdings Inc
PHI Merger Commitments [Line Items]
Other Commitment	320
Potomac Electric Power Company
PHI Merger Commitments [Line Items]
Other Commitment	93
Potomac Electric Power Company | PEPCO Holdings Inc
PHI Merger Commitments [Line Items]
Other Commitment	120
Delmarva Power & Light Company
PHI Merger Commitments [Line Items]
Other Commitment	18
Delmarva Power & Light Company | PEPCO Holdings Inc
PHI Merger Commitments [Line Items]
Other Commitment	89
Atlantic City Electric Company
PHI Merger Commitments [Line Items]
Other Commitment	12
Atlantic City Electric Company | PEPCO Holdings Inc
PHI Merger Commitments [Line Items]
Other Commitment	111
Remaining Commitment [Member] | PEPCO Holdings Inc
PHI Merger Commitments [Line Items]
Other Commitment	38
Remaining Commitment [Member] | Pepco Holdings LLC | PEPCO Holdings Inc
PHI Merger Commitments [Line Items]
Other Commitment	35
Remaining Commitment [Member] | Potomac Electric Power Company | PEPCO Holdings Inc
PHI Merger Commitments [Line Items]
Other Commitment	31
Remaining Commitment [Member] | Delmarva Power & Light Company | PEPCO Holdings Inc
PHI Merger Commitments [Line Items]
Other Commitment	3
Remaining Commitment [Member] | Atlantic City Electric Company | PEPCO Holdings Inc
PHI Merger Commitments [Line Items]
Other Commitment	1
Guarantee Obligations [Member]
PHI Merger Commitments [Line Items]
Other Commitment	27
Guarantee Obligations [Member] | Pepco Holdings LLC
PHI Merger Commitments [Line Items]
Other Commitment	27
Guarantee Obligations [Member] | Potomac Electric Power Company
PHI Merger Commitments [Line Items]
Other Commitment	9
Guarantee Obligations [Member] | Delmarva Power & Light Company
PHI Merger Commitments [Line Items]
Other Commitment	11
Guarantee Obligations [Member] | Atlantic City Electric Company
PHI Merger Commitments [Line Items]
Other Commitment	$ 7