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Income Taxes (Narrative) (Details) | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Income Tax [Line Items] |  |  |
Overall income tax rate | (12.00%) | (10.00%) | 11.00%
IPL [Member] |  |  |
Income Tax [Line Items] |  |  |
Overall income tax rate | (11.00%) | (16.00%) | 8.00%
WPL [Member] |  |  |
Income Tax [Line Items] |  |  |
Overall income tax rate | (24.00%) | (8.00%) | 17.00%
State [Member] |  |  |
Income Tax [Line Items] |  |  |
Overall income tax rate | 9.80% | 12.00% |
State [Member] | IPL [Member] |  |  |
Income Tax [Line Items] |  |  |
Overall income tax rate | 9.80% | 12.00% |
State [Member] | WPL [Member] |  |  |
Income Tax [Line Items] |  |  |
Overall income tax rate | 9.80% | 12.00% |

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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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