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Benefit Plans (Recognized Compensation Expense And Income Tax Benefits) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Compensation expense | $ 3 | $ 3 | $ 6 | $ 7
Income tax benefits | 1 | 1 | 2 | 2
IPL [Member] |  |  |  |
Compensation expense | 2 | 1 | 3 | 4
Income tax benefits | 0 | 0 | 1 | 1
WPL [Member] |  |  |  |
Compensation expense | 1 | 1 | 2 | 3
Income tax benefits | $ 0 | $ 0 | $ 1 | $ 1

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