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Subsequent Events (Details) - MW	Jan. 01, 2022	Dec. 31, 2021
Purchase Power Contract, MEAN
Subsequent Event [Line Items]
Megawatts Sold Under Long-Term Contract		20
Subsequent Event | Tri-State Generation and Transmission Association | Black Hills Energy - Colorado Electric
Subsequent Event [Line Items]
Megawatts Sold Under Long-Term Contract	58
Subsequent Event | Purchase Power Contract, MEAN | Black Hills Energy - South Dakota Electric
Subsequent Event [Line Items]
Megawatts Sold Under Long-Term Contract	20

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- Definition

Number of Megawatts Sold Under Long-Term Contract

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

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- Details

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Namespace Prefix:
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X

- Details

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X

- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

X

- Details

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Namespace Prefix:
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X

- Details

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