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Regulatory Matters - Energy Efficiency Formula Rate (Details) - Commonwealth Edison Co
$ in Millions
9 Months Ended
May 30, 2024
USD ($)
Feb. 03, 2022
Sep. 30, 2023
Schedule of Energy Efficiency Formula Rate Updates [Line Items]      
Basis points for ComEd's Revenue Requirement   580  
ComEd 2024 Energy Efficiency Formula Rate      
Schedule of Energy Efficiency Formula Rate Updates [Line Items]      
Public Utilities, Requested Rate Increase (Decrease), Amount $ 66    
Public Utilities Requested Rate Increase (Decrease), Prior Year Annual Reconciliation (8)    
Public Utilities, Requested Rate Increase (Decrease), Amended, Amount $ 58    
Public Utilities, Requested Equity Capital Structure, Percentage 7.02%    
Requested Return on Equity, Percentage 9.89%    
ComEd 2024 Energy Efficiency Formula Rate | 2024      
Schedule of Energy Efficiency Formula Rate Updates [Line Items]      
Basis points for ComEd's Revenue Requirement 580    
ComEd 2023 Energy Efficiency Formula Rate      
Schedule of Energy Efficiency Formula Rate Updates [Line Items]      
Public Utilities, Approved Equity Capital Structure, Percentage     7.25%
Public Utilities, Approved Return on Equity, Percentage     10.34%