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Commitments, Contingencies and Guarantees: Power Purchase Agreements (Details) - Solar - MW	Mar. 21, 2022	Feb. 19, 2021
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

Number of Megawatts Capacity Purchased

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No definition available.

+ Details

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X

- 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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- 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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- Details

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