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Benefit Plans (Recognized Compensation Expense And Income Tax Benefits) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Compensation expense | $ 13 | $ 14 | $ 16
Income tax benefits | 3 | 4 | 4
IPL [Member] |  |  |
Compensation expense | 7 | 8 | 9
Income tax benefits | 2 | 2 | 2
WPL [Member] |  |  |
Compensation expense | 5 | 6 | 6
Income tax benefits | $ 1 | $ 2 | $ 2

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