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Income Taxes (Schedule Of Components Of Income Tax) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Current tax expense (benefit): |  |  |
Federal | $ 1 | $ 1 | $ (7)
State | 3 | 8 | 24
Deferred tax expense (benefit): |  |  |
Federal | 9 | 22 | 70
State | 15 | 8 | 42
Production tax credits | (101) | (95) | (55)
Investment tax credits | (1) | (1) | (1)
Income tax expense (benefit) | (74) | (57) | 69
IPL's tax benefit riders [Member] |  |  |
Current tax expense (benefit): |  |  |
IPL's tax benefit riders | 0 | 0 | (4)
IPL [Member] |  |  |
Current tax expense (benefit): |  |  |
Federal | (21) | 6 | (11)
State | (1) | (1) | 24
Deferred tax expense (benefit): |  |  |
Federal | 73 | 30 | 26
State | 0 | (2) | 31
Production tax credits | (87) | (80) | (42)
Investment tax credits | 0 | 0 | 0
Income tax expense (benefit) | (36) | (47) | 24
IPL [Member] | IPL's tax benefit riders [Member] |  |  |
Current tax expense (benefit): |  |  |
IPL's tax benefit riders | 0 | 0 | (4)
WPL [Member] |  |  |
Current tax expense (benefit): |  |  |
Federal | 22 | (11) | 12
State | 6 | 7 | 13
Deferred tax expense (benefit): |  |  |
Federal | (75) | (9) | 31
State | 11 | 10 | 6
Production tax credits | (14) | (15) | (13)
Investment tax credits | (1) | (1) | 0
Income tax expense (benefit) | $ (51) | $ (19) | $ 49

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