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Income Taxes (Schedule Of Components Of Income Tax) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Current tax expense (benefit): |  |  |
Federal | $ (6.6) | $ (1.0) | $ (41.0)
State | 24.2 | (5.1) | 8.5
Deferred tax expense (benefit): |  |  |
Federal | 69.7 | 67.9 | 159.5
State | 41.4 | 29.8 | 12.3
Production tax credits | (54.7) | (29.5) | (31.1)
Investment tax credits | (0.8) | (1.2) | (1.1)
Income tax expense (benefit) | 68.7 | 47.7 | 66.7
IPL's tax benefit riders [Member] |  |  |
Current tax expense (benefit): |  |  |
IPL's tax benefit riders | (4.5) | (13.2) | (40.4)
IPL [Member] |  |  |
Current tax expense (benefit): |  |  |
Federal | (11.0) | 14.9 | (27.9)
State | 24.3 | (7.1) | 1.6
Deferred tax expense (benefit): |  |  |
Federal | 26.4 | 9.5 | 72.5
State | 30.9 | 7.3 | (2.2)
Production tax credits | (41.8) | (14.0) | (14.1)
Investment tax credits | (0.2) | (0.6) | (0.4)
Income tax expense (benefit) | 24.1 | (3.2) | (10.9)
IPL [Member] | IPL's tax benefit riders [Member] |  |  |
Current tax expense (benefit): |  |  |
IPL's tax benefit riders | (4.5) | (13.2) | (40.4)
WPL [Member] |  |  |
Current tax expense (benefit): |  |  |
Federal | 12.0 | (9.2) | 5.5
State | 13.7 | (4.4) | 2.5
Deferred tax expense (benefit): |  |  |
Federal | 30.7 | 43.8 | 55.0
State | 6.3 | 22.1 | 16.6
Production tax credits | (12.8) | (15.5) | (17.0)
Investment tax credits | (0.6) | (0.6) | (0.7)
Income tax expense (benefit) | $ 49.3 | $ 36.2 | $ 61.9

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