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Derivative Financial Instruments - Summary of Counterparty Collateral (Details) - USD ($) $ in Millions | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Other | $ 569 | $ 557
Baltimore Gas and Electric Company |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Other | 48 | 9
External Counterparties | Commodity Contract [Member] | Collateral [Member] |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Other | 170 | 148
External Counterparties | Commodity Contract [Member] | Collateral [Member] | Commonwealth Edison Co |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Other | 167 | 146
External Counterparties | Commodity Contract [Member] | Collateral [Member] | PECO Energy Co |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Other | 0 | 0
External Counterparties | Commodity Contract [Member] | Collateral [Member] | Baltimore Gas and Electric Company |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Other | 1 | 1
External Counterparties | Commodity Contract [Member] | Collateral [Member] | Pepco Holdings LLC |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Other | 2 | 1
External Counterparties | Commodity Contract [Member] | Collateral [Member] | Potomac Electric Power Company |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Other | 0 | 1
External Counterparties | Commodity Contract [Member] | Collateral [Member] | Delmarva Power and Light Company |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Other | 2 | 0
External Counterparties | Commodity Contract [Member] | Collateral [Member] | Atlantic City Electric Company |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Other | $ 0 | $ 0

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