Regulatory Matters - Energy Efficiency Formula Rate (Details) - Commonwealth Edison Co - USD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
May 29, 2026 |
Dec. 31, 2025 |
|
| ComEd 2026 Energy Efficiency Formula Rate | ||
| Schedule of Energy Efficiency Formula Rate Updates [Line Items] | ||
| Public Utilities, Requested Rate Increase (Decrease), Amount | $ 28 | |
| Public Utilities Requested Rate Increase (Decrease), Prior Year Annual Reconciliation | (56) | |
| Public Utilities, Requested Rate Increase (Decrease), Amended, Amount | $ (28) | |
| Public Utilities, Requested Equity Capital Structure, Percentage | 6.62% | |
| Requested Return on Equity, Percentage | 8.905% | |
| CmEd 2025 Energy Efficiency Formula Rate | ||
| Schedule of Energy Efficiency Formula Rate Updates [Line Items] | ||
| Public Utilities, Approved Equity Capital Structure, Percentage | 7.67% | |
| Public Utilities, Approved Return on Equity, Percentage | 11.00% |