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Commitments, Contingencies and Guarantees - Transmission Service Agreements (Details) | Jan. 01, 2022 MW
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Colorado Electric | Tri-State Generation and Transmission Association |
Unrecorded Unconditional Purchase Obligation [Line Items] |
Number of Megawatts Sold Under Long-Term Contract | 58
South Dakota Electric | Purchase Power Contract, MEAN |
Unrecorded Unconditional Purchase Obligation [Line Items] |
Number of Megawatts Sold Under Long-Term Contract | 20

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