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Income Taxes (Schedule Of Effective Income Tax Rates) (Details) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Effective Tax Rate [Line Items] |  |  |  |
Overall income tax rate | (9.00%) | (9.00%) | (13.00%) | (9.00%)
IPL [Member] |  |  |  |
Effective Tax Rate [Line Items] |  |  |  |
Overall income tax rate | (8.00%) | (14.00%) | (11.00%) | (14.00%)
WPL [Member] |  |  |  |
Effective Tax Rate [Line Items] |  |  |  |
Overall income tax rate | (19.00%) | (7.00%) | (24.00%) | (8.00%)

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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319 + Details
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