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Benefit Plans (Recognized Compensation Expense And Income Tax Benefits) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Compensation expense | $ 12 | $ 13 | $ 14
Income tax benefits | 3 | 3 | 4
IPL [Member] |  |  |
Compensation expense | 6 | 7 | 8
Income tax benefits | 2 | 2 | 2
WPL [Member] |  |  |
Compensation expense | 5 | 5 | 6
Income tax benefits | $ 1 | $ 1 | $ 2

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