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Commitments and Contingencies - Narrative (Details) - USD ($) $ in Millions | 1 Months Ended | 9 Months Ended
--- | --- | ---
Nov. 30, 2020 | Sep. 30, 2024
Commonwealth Edison Co |  |
Commitments And Contingencies Additional Narrative Information [Line Items] |  |
Mgp Site Contingency Monitoring Count |  | 16
Deferred Prosecution Agreement Payments | $ 200.0 |
Loss Contingency Accrual |  | $ 46.2
Customer Refund Liability, Current |  | 38.0
Commonwealth Edison Co | Accrual For MGP Investigation And Remediation |  |
Commitments And Contingencies Additional Narrative Information [Line Items] |  |
Accrual for Environmental Loss Contingencies, Period Increase (Decrease) |  | 13.0
Commonwealth Edison Co | Illinois Chamber of Commerce |  |
Commitments And Contingencies Additional Narrative Information [Line Items] |  |
Customer Refund Liability, Current |  | $ 31.0
PECO Energy Co |  |
Commitments And Contingencies Additional Narrative Information [Line Items] |  |
Mgp Site Contingency Monitoring Count |  | 6
PECO Energy Co | Accrual For MGP Investigation And Remediation |  |
Commitments And Contingencies Additional Narrative Information [Line Items] |  |
Accrual for Environmental Loss Contingencies, Period Increase (Decrease) |  | $ 4.0
Baltimore Gas and Electric Company |  |
Commitments And Contingencies Additional Narrative Information [Line Items] |  |
Mgp Site Contingency Monitoring Count |  | 4
Delmarva Power and Light Company |  |
Commitments And Contingencies Additional Narrative Information [Line Items] |  |
Mgp Site Contingency Monitoring Count |  | 1
Potomac Electric Power Company |  |
Commitments And Contingencies Additional Narrative Information [Line Items] |  |
Environmental Liability - Anacostia |  | $ 47.0
Environmental Liability - Buzzard Point |  | 10.0
Exelon Business Services Co Affiliate |  |
Commitments And Contingencies Additional Narrative Information [Line Items] |  |
Deferred Prosecution Agreement Liability, Current |  | 173.0
Insurers' Settlement Payment |  | 40.0
Settling Shareholders' Attorney Fees |  | $ 10.0

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