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Jointly-Owned Facilities and Assets | 12 Months Ended
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Dec. 31, 2022
Jointly-Owned Facilities and Assets [Abstract] |
Jointly-Owned Facilities and Assets [Text Block] | JOINTLY-OWNED FACILITIES AND ASSETS Boswell Unit 4. Minnesota Power owns 80 percent of the 585 MW Boswell Unit 4. While Minnesota Power operates the plant, certain decisions about the operations of Boswell Unit 4 are subject to the oversight of a committee on which it and WPPI Energy, the owner of the remaining 20 percent, have equal representation and voting rights. Each owner must provide its own financing and is obligated to its ownership share of operating costs. Minnesota Power’s share of operating expenses for Boswell Unit 4 is included in Operating Expenses on the Consolidated Statement of Income. Minnesota Power’s investments in jointly-owned facilities and assets and the related ownership percentages are as follows:
Regulated Utility Plant | Plant in Service | Accumulated Depreciation | Construction Work in Progress | % Ownership
Millions |  |  |  |
As of December 31, 2022 |  |  |  |
Boswell Unit 4 | $712.0 | $340.1 | $3.3 | 80
Transmission Assets | 101.0 | 21.1 | — | 9.3 - 14.7
Total | $813.0 | $361.2 | $3.3 |
As of December 31, 2021 |  |  |  |
Boswell Unit 4 | $682.7 | $311.1 | $30.1 | 80
Transmission Assets | 101.0 | 18.5 | — | 9.3 - 14.7
Total | $783.7 | $329.6 | $30.1 |

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- Definition Jointly-Owned Electric Facility [Text Block] + References No definition available. + Details
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- Definition Jointly-Owned Facilities and Assets [Abstract] + References No definition available. + Details
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