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Derivative Instruments (Notional Amounts Of Derivative Instruments) (Details) - Commodity [Member] T in Thousands, MWh in Thousands, Dekatherms in Thousands | 3 Months Ended
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Mar. 31, 2023 Dekatherms MWh T
Electricity (MWhs) [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in MWhs) | 922
Electricity (MWhs) [Member] | IPL [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in MWhs) | 391
Electricity (MWhs) [Member] | WPL [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in MWhs) | 531
FTRs (MWhs) [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in MWhs) | 3,276
FTRs (MWhs) [Member] | IPL [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in MWhs) | 1,338
FTRs (MWhs) [Member] | WPL [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in MWhs) | 1,938
Natural Gas (Dths) [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in Dths) | Dekatherms | 209,102
Natural Gas (Dths) [Member] | IPL [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in Dths) | Dekatherms | 101,863
Natural Gas (Dths) [Member] | WPL [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in Dths) | Dekatherms | 107,239
Coal (Tons) [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in Tons) | T | 662
Coal (Tons) [Member] | IPL [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in Tons) | T | 325
Coal (Tons) [Member] | WPL [Member] |
Notional Amount of Derivatives [Line Items] |
Notional unit amount of derivatives (in Tons) | T | 337

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