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Benefit Plans (Estimated Future Funding) (Details) - Forecast [Member] $ in Millions | Dec. 31, 2024 USD ($)
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Defined Benefit Pension Plans [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Estimated funding for calendar year 2024 | $ 12
Defined Benefit Pension Plans [Member] | IPL [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Estimated funding for calendar year 2024 | 0
Defined Benefit Pension Plans [Member] | WPL [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Estimated funding for calendar year 2024 | 10
Other Postretirement Benefits Plans [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Estimated funding for calendar year 2024 | 8
Other Postretirement Benefits Plans [Member] | IPL [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Estimated funding for calendar year 2024 | 1
Other Postretirement Benefits Plans [Member] | WPL [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Estimated funding for calendar year 2024 | $ 6

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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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- Definition Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-18 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (g) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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- Details
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- Details
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- Details
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