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Benefit Plans (Recognized Compensation Expense And Income Tax Benefits) (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Compensation expense | $ 4 | $ 3
Income tax benefits | 1 | 1
IPL [Member] |  |
Compensation expense | 2 | 2
Income tax benefits | 1 | 0
WPL [Member] |  |
Compensation expense | 2 | 1
Income tax benefits | $ 0 | $ 0

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