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Income Taxes (Schedule Of Components Of Income Tax) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Current tax expense (benefit): |  |  |
Federal | $ (1.0) | $ (41.0) | $ 1.8
State | (5.1) | 8.5 | 17.2
Deferred tax expense (benefit): |  |  |
Federal | 67.9 | 159.5 | 112.8
State | 29.8 | 12.3 | 4.9
Production tax credits | (29.5) | (31.1) | (31.8)
Investment tax credits | (1.2) | (1.1) | (1.3)
Income tax expense (benefit) | 47.7 | 66.7 | 59.4
IPL's tax benefit riders [Member] |  |  |
Current tax expense (benefit): |  |  |
IPL's tax benefit riders | (13.2) | (40.4) | (44.2)
IPL [Member] |  |  |
Current tax expense (benefit): |  |  |
Federal | 14.9 | (27.9) | (12.8)
State | (7.1) | 1.6 | 15.5
Deferred tax expense (benefit): |  |  |
Federal | 9.5 | 72.5 | 59.1
State | 7.3 | (2.2) | (9.0)
Production tax credits | (14.0) | (14.1) | (14.0)
Investment tax credits | (0.6) | (0.4) | (0.5)
Income tax expense (benefit) | (3.2) | (10.9) | (5.9)
IPL [Member] | IPL's tax benefit riders [Member] |  |  |
Current tax expense (benefit): |  |  |
IPL's tax benefit riders | (13.2) | (40.4) | (44.2)
WPL [Member] |  |  |
Current tax expense (benefit): |  |  |
Federal | (9.2) | 5.5 | (22.3)
State | (4.4) | 2.5 | 1.1
Deferred tax expense (benefit): |  |  |
Federal | 43.8 | 55.0 | 112.3
State | 22.1 | 16.6 | 20.8
Production tax credits | (15.5) | (17.0) | (17.8)
Investment tax credits | (0.6) | (0.7) | (0.8)
Income tax expense (benefit) | $ 36.2 | $ 61.9 | $ 93.3

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- Definition Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 6.I.7) -URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319 + Details
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