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Benefit Plans (Recognized Compensation Expense And Income Tax Benefits) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Compensation expense | $ 6 | $ 3 | $ 13 | $ 10
Income tax benefits | 2 | 1 | 4 | 3
IPL [Member] |  |  |  |
Compensation expense | 3 | 2 | 7 | 5
Income tax benefits | 1 | 0 | 2 | 1
WPL [Member] |  |  |  |
Compensation expense | 2 | 1 | 6 | 4
Income tax benefits | $ 1 | $ 0 | $ 2 | $ 1

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