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Jointly-Owned Electric Utility Plant (Details) $ in Millions | Dec. 31, 2024 USD ($)
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Jointly Owned Electric Utility Plant [Line Items] |
Electric Plant | $ 2,496
Accumulated Provision for Depreciation | 992
Construction Work in Progress | 45
IPL [Member] |
Jointly Owned Electric Utility Plant [Line Items] |
Electric Plant | 1,069
Accumulated Provision for Depreciation | 499
Construction Work in Progress | 34
WPL [Member] |
Jointly Owned Electric Utility Plant [Line Items] |
Electric Plant | 1,427
Accumulated Provision for Depreciation | 493
Construction Work in Progress | $ 11
Ottumwa Unit 1 [Member] | IPL [Member] |
Jointly Owned Electric Utility Plant [Line Items] |
Ownership Interest % | 48.00%
Electric Plant | $ 648
Accumulated Provision for Depreciation | 277
Construction Work in Progress | $ 7
George Neal Unit 4 [Member] | IPL [Member] |
Jointly Owned Electric Utility Plant [Line Items] |
Ownership Interest % | 25.70%
Electric Plant | $ 197
Accumulated Provision for Depreciation | 110
Construction Work in Progress | $ 7
George Neal Unit 3 [Member] | IPL [Member] |
Jointly Owned Electric Utility Plant [Line Items] |
Ownership Interest % | 28.00%
Electric Plant | $ 181
Accumulated Provision for Depreciation | 89
Construction Work in Progress | $ 20
Louisa Unit 1 [Member] | IPL [Member] |
Jointly Owned Electric Utility Plant [Line Items] |
Ownership Interest % | 4.00%
Electric Plant | $ 43
Accumulated Provision for Depreciation | 23
Construction Work in Progress | $ 0
Columbia Units 1-2 and Energy Storage System [Member] | WPL [Member] |
Jointly Owned Electric Utility Plant [Line Items] |
Ownership Interest % | 53.50%
Electric Plant | $ 859
Accumulated Provision for Depreciation | 378
Construction Work in Progress | $ 6
West Riverside Energy Center and Solar Facility [Member] | WPL [Member] |
Jointly Owned Electric Utility Plant [Line Items] |
Ownership Interest % | 56.60%
Electric Plant | $ 449
Accumulated Provision for Depreciation | 59
Construction Work in Progress | $ 5
Forward Wind Energy Center [Member] | WPL [Member] |
Jointly Owned Electric Utility Plant [Line Items] |
Ownership Interest % | 42.60%
Electric Plant | $ 119
Accumulated Provision for Depreciation | 56
Construction Work in Progress | $ 0

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- Definition The period end amount owned by the reporting utility of a jointly owned utility plant in service. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 360 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.C) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479070/980-360-S99-1 + 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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- Definition The period end amount of construction work in progress at a jointly owned electricity generation plant. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 360 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.C) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479070/980-360-S99-1 + Details
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- Definition The period end amount of accumulated depreciation in a jointly owned electricity generation plant. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 360 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.C) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479070/980-360-S99-1 + Details
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- Definition The proportionate share of interest (percent) in a jointly owned utility plant. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 360 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.C) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479070/980-360-S99-1 + Details
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