v3.26.3
Income Taxes - Narrative (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Feb. 18, 2026
Aug. 16, 2022
Jun. 30, 2026
Mar. 31, 2026
Sep. 30, 2026
Sep. 30, 2025
Dec. 31, 2025
Income Tax Narrative Information [Line Items]              
Other accounts receivable, net         $ 1,478   $ 1,785
Tax Jurisdiction of Domicile [Extensible Enumeration]         ILLINOIS, MARYLAND ILLINOIS, MARYLAND  
Tax Year 2024              
Income Tax Narrative Information [Line Items]              
Income Taxes Receivable, Current $ 80            
Tax Year 2023              
Income Tax Narrative Information [Line Items]              
Income Taxes Receivable, Current 80            
Constellation Energy Corp              
Income Tax Narrative Information [Line Items]              
Other Income $ 235            
Constellation Energy Corp              
Income Tax Narrative Information [Line Items]              
Notes payable, current         $ 106    
Notes payable, noncurrent         271    
Constellation Energy Corp | General Business Tax Credit Carryforward              
Income Tax Narrative Information [Line Items]              
Separation Cash Received       $ 235      
Separation Cash Payment     $ 53        
Constellation Energy Corp | Indemnification for Taxes              
Income Tax Narrative Information [Line Items]              
Other accounts receivable, net         0    
Other Liabilities         0    
Constellation Energy Corp | Tax Refunds              
Income Tax Narrative Information [Line Items]              
Other accounts receivable, net         0    
Other Liabilities         0    
Commonwealth Edison Co              
Income Tax Narrative Information [Line Items]              
Other accounts receivable, net         $ 449   1,132
Tax Jurisdiction of Domicile [Extensible Enumeration]         ILLINOIS ILLINOIS  
PECO Energy Co              
Income Tax Narrative Information [Line Items]              
Other accounts receivable, net         $ 348   126
Tax Jurisdiction of Domicile [Extensible Enumeration]         PENNSYLVANIA PENNSYLVANIA  
Baltimore Gas and Electric Company              
Income Tax Narrative Information [Line Items]              
Other accounts receivable, net         $ 144   96
Tax Jurisdiction of Domicile [Extensible Enumeration]         MARYLAND MARYLAND  
Pepco Holdings LLC              
Income Tax Narrative Information [Line Items]              
Other accounts receivable, net         $ 266   243
Tax Jurisdiction of Domicile [Extensible Enumeration]         MARYLAND, NEW JERSEY MARYLAND, NEW JERSEY  
Potomac Electric Power Company              
Income Tax Narrative Information [Line Items]              
Other accounts receivable, net         $ 131   128
Tax Jurisdiction of Domicile [Extensible Enumeration]         MARYLAND MARYLAND  
Delmarva Power and Light Company              
Income Tax Narrative Information [Line Items]              
Other accounts receivable, net         $ 62   65
Tax Jurisdiction of Domicile [Extensible Enumeration]         DELAWARE DELAWARE  
Atlantic City Electric Company              
Income Tax Narrative Information [Line Items]              
Other accounts receivable, net         $ 72   $ 51
Tax Jurisdiction of Domicile [Extensible Enumeration]         NEW JERSEY NEW JERSEY  
US Treasury (UST) Interest Rate              
Income Tax Narrative Information [Line Items]              
Nontaxable or nondeductible items   15.00%