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Income Taxes (Schedule Of Effective Income Tax Rates) (Details) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Effective Tax Rate [Line Items] |  |  |  |
Overall income tax rate, percent | (7.00%) | (27.00%) | (19.00%) | (24.00%)
IPL [Member] |  |  |  |
Effective Tax Rate [Line Items] |  |  |  |
Overall income tax rate, percent | (15.00%) | (56.00%) | (36.00%) | (70.00%)
WPL [Member] |  |  |  |
Effective Tax Rate [Line Items] |  |  |  |
Overall income tax rate, percent | 1.00% | 3.00% | (3.00%) | 5.00%

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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 -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-12 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 231 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482663/740-10-55-231 + Details
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