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Income Taxes - Narrative (Details) - USD ($) $ in Millions | Aug. 16, 2022 | Sep. 30, 2024
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Income Tax Additional Narrative Information [Line Items] |  |
Notes payable, current |  | $ 130
Notes payable, noncurrent |  | 201
Tax credit carryforward, valuation allowance |  | 0
Commonwealth Edison Co |  |
Income Tax Additional Narrative Information [Line Items] |  |
Tax credit carryforward, valuation allowance |  | 0
PECO Energy Co |  |
Income Tax Additional Narrative Information [Line Items] |  |
Tax credit carryforward, valuation allowance |  | 0
Baltimore Gas and Electric Company |  |
Income Tax Additional Narrative Information [Line Items] |  |
Tax credit carryforward, valuation allowance |  | 0
Pepco Holdings LLC |  |
Income Tax Additional Narrative Information [Line Items] |  |
Tax credit carryforward, valuation allowance |  | 0
Potomac Electric Power Company |  |
Income Tax Additional Narrative Information [Line Items] |  |
Tax credit carryforward, valuation allowance |  | 0
Delmarva Power and Light Company |  |
Income Tax Additional Narrative Information [Line Items] |  |
Tax credit carryforward, valuation allowance |  | 0
Atlantic City Electric Company |  |
Income Tax Additional Narrative Information [Line Items] |  |
Tax credit carryforward, valuation allowance |  | $ 0
US Treasury (UST) Interest Rate |  |
Income Tax Additional Narrative Information [Line Items] |  |
Excess deferred tax amortization | 15.00% |

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