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Leases (Liabilities Arising from Obtaining Leased Assets (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022
Leases [Line Items] |  |
Finance lease liabilities arising from obtaining leased assets | $ 34 | $ 125
IPL [Member] |  |
Leases [Line Items] |  |
Finance lease liabilities arising from obtaining leased assets | 33 | 0
WPL [Member] |  |
Leases [Line Items] |  |
Finance lease liabilities arising from obtaining leased assets | $ 71 | $ 125

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- Definition Amount of increase in right-of-use asset obtained in exchange for finance lease liability. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 53 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479589/842-20-55-53 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (g)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147478964/842-20-50-4 + Details
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- Details
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