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Receivables (Narrative) (Details) - Receivables Sold [Member] - IPL [Member] - USD ($) $ in Millions | Dec. 31, 2023 | Oct. 31, 2023 | Sep. 30, 2023
--- | --- | --- | ---
Receivables [Line Items] |  |  |
Available capacity |  |  | $ 109
Subsequent Event [Member] |  |  |
Receivables [Line Items] |  |  |
Available capacity | $ 110 | $ 5 |
Financial Asset, Past Due [Member] |  |  |
Receivables [Line Items] |  |  |
Outstanding receivables past due |  |  | $ 18

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