Regulatory Matters - Annual Electric Transmission Fillings (Details) - USD ($) $ in Millions	May 27, 2026	May 15, 2026
Commonwealth Edison Co \| 2026 Transmission Formula Rate Annual Update
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount		$ 31
Annual Reconciliation Increase (Decrease)		(52)
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount		$ (21)
Public Utilities, Approved Equity Capital Structure, Percentage		8.15%
Public Utilities, Approved Return on Equity, Percentage		11.50%
Basis points for Transmission Formula Rate		0.0050
PECO Energy Co \| 2026 Transmission Formula Rate Annual Update
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount	$ 20
Annual Reconciliation Increase (Decrease)	20
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount	$ 40
Public Utilities, Approved Equity Capital Structure, Percentage	7.62%
Public Utilities, Approved Return on Equity, Percentage	10.35%
Basis points for Transmission Formula Rate	0.0050
Baltimore Gas and Electric Company \| 2026 Transmission Formula Rate Annual Update
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount		$ 16
Annual Reconciliation Increase (Decrease)		(40)
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount		$ (30)
Public Utilities, Approved Equity Capital Structure, Percentage		7.51%
Public Utilities, Approved Return on Equity, Percentage		10.50%
Basis points for Transmission Formula Rate		0.0050
Baltimore Gas and Electric Company \| 2026 Transmission Formula Rate Revenue Reduction
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount		$ (6)
Potomac Electric Power Company \| 2026 Transmission Formula Rate Annual Update
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount		12
Annual Reconciliation Increase (Decrease)		(21)
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount		$ (9)
Public Utilities, Approved Equity Capital Structure, Percentage		7.72%
Public Utilities, Approved Return on Equity, Percentage		10.50%
Basis points for Transmission Formula Rate		0.0050
Delmarva Power and Light Company \| 2026 Transmission Formula Rate Annual Update
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount		$ 3
Annual Reconciliation Increase (Decrease)		1
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount		$ 4
Public Utilities, Approved Equity Capital Structure, Percentage		7.53%
Public Utilities, Approved Return on Equity, Percentage		10.50%
Basis points for Transmission Formula Rate		0.0050
Atlantic City Electric Company \| 2026 Transmission Formula Rate Annual Update
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount		$ 1
Annual Reconciliation Increase (Decrease)		16
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount		$ 17
Public Utilities, Approved Equity Capital Structure, Percentage		7.26%
Public Utilities, Approved Return on Equity, Percentage		10.50%
Basis points for Transmission Formula Rate		0.0050

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