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Valuation And Qualifying Accounts and Reserves (Details) - Accumulated Provision for Uncollectible Accounts [Member] - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Beginning Balance | $ 8.0 | $ 7.0 | $ 11.0
Additions (Charged to Expense) | 24.0 | 20.0 | 17.0
Deductions | 24.0 | 19.0 | 21.0
Ending Balance | 8.0 | 8.0 | 7.0
IPL [Member] |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Beginning Balance | 0.0 | 0.0 | 1.0
Additions (Charged to Expense) | 13.0 | 11.0 | 7.0
Deductions | 13.0 | 11.0 | 8.0
Ending Balance | 0.0 | 0.0 | 0.0
WPL [Member] |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Beginning Balance | 8.0 | 7.0 | 10.0
Additions (Charged to Expense) | 11.0 | 9.0 | 10.0
Deductions | 11.0 | 8.0 | 13.0
Ending Balance | $ 8.0 | $ 8.0 | $ 7.0

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