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Commitments, Contingencies and Guarantees: Power Purchase Agreements (Details) - Solar - MW | Jun. 23, 2022 | Mar. 21, 2022 | Feb. 19, 2021
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Roundhouse Renewable Energy II, LLC | Wyoming Electric |  |  |
Unrecorded Unconditional Purchase Obligation [Line Items] |  |  |
Number of Megawatts Capacity Purchased | 106 |  |
Purchase Power Agreement Set to Expire after a Certain Number of Years Following Completion of the Facility | 20 years |  |
South Cheyenne Solar, LLC | Wyoming Electric |  |  |
Unrecorded Unconditional Purchase Obligation [Line Items] |  |  |
Number of Megawatts Capacity Purchased |  | 150 |
Purchase Power Agreement Set to Expire after a Certain Number of Years Following Completion of the Facility |  | 20 years |
TC Colorado Solar, LLC | Colorado Electric |  |  |
Unrecorded Unconditional Purchase Obligation [Line Items] |  |  |
Number of Megawatts Capacity Purchased |  |  | 200

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- Definition Purchase Power Agreement Set to Expire after a Certain Number of Years Following Completion of the Facility + References No definition available. + Details
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