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Derivative Instruments (Notional Amounts Of Derivative Instruments) (Details) - Commodity [Member] | 3 Months Ended
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Mar. 31, 2024 Dekatherms MWh
Electricity (MWhs) [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in MWhs) | 1,412
Electricity (MWhs) [Member] | IPL [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in MWhs) | 673
Electricity (MWhs) [Member] | WPL [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in MWhs) | 739
FTRs (MWhs) [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in MWhs) | 4,162
FTRs (MWhs) [Member] | IPL [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in MWhs) | 1,444
FTRs (MWhs) [Member] | WPL [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in MWhs) | 2,718
Natural Gas (Dths) [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in Dths) | Dekatherms | 173,746
Natural Gas (Dths) [Member] | IPL [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in Dths) | Dekatherms | 78,790
Natural Gas (Dths) [Member] | WPL [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in Dths) | Dekatherms | 94,956

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