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Summary Of Significant Accounting Policies (Schedule Of Allowance For Funds Used During Construction Recovery Rate) (Details) | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
IPL [Member] |  |  |
Public Utility, Property, Plant and Equipment [Line Items] |  |  |
Recovery rates, percent | 7.00% | 7.00% | 7.00%
WPL [Member] | WPL (retail jurisdiction) [Member] |  |  |
Public Utility, Property, Plant and Equipment [Line Items] |  |  |
Recovery rates, percent | 7.40% | 7.40% | 7.00%
WPL [Member] | WPL (wholesale jurisdiction) [Member] |  |  |
Public Utility, Property, Plant and Equipment [Line Items] |  |  |
Recovery rates, percent | 7.10% | 7.10% | 6.20%

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- Definition Effective rate, including composite rate, of cost of financing additions to qualifying regulated assets, commonly called allowance for funds used during construction. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 980 -SubTopic 835 -Section 25 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478698/980-835-25-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 980 -SubTopic 835 -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479123/980-835-45-1 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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