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Jointly-Owned Facilities and Assets - Table (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Jointly-Owned Facilities and Assets [Line Items] |  |
Plant in Service | $ 826.9 | $ 813.0
Accumulated Depreciation | 393.4 | 361.2
Construction Work in Progress | 2.8 | 3.3
Transmission Assets | Transmission Assets |  |
Jointly-Owned Facilities and Assets [Line Items] |  |
Plant in Service | 101.0 | 101.0
Accumulated Depreciation | 23.6 | 21.1
Construction Work in Progress | $ 0.0 | $ 0.0
Transmission Assets | Transmission Assets | Minimum |  |
Jointly-Owned Facilities and Assets [Line Items] |  |
% Ownership | 9.30% | 9.30%
Transmission Assets | Transmission Assets | Maximum |  |
Jointly-Owned Facilities and Assets [Line Items] |  |
% Ownership | 14.70% | 14.70%
Boswell Unit 4 | Boswell Unit 4 |  |
Jointly-Owned Facilities and Assets [Line Items] |  |
Plant in Service | $ 725.9 | $ 712.0
Accumulated Depreciation | 369.8 | 340.1
Construction Work in Progress | $ 2.8 | $ 3.3
% Ownership | 80.00% | 80.00%

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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//1943274/2147479960/980-360-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//1943274/2147479960/980-360-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//1943274/2147479960/980-360-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//1943274/2147479960/980-360-S99-1 + Details
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