Jointly Owned Facilities (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Wyodak Plant
Jointly Owned Utility Plant Interests [Line Items]
Ownership Interest	20.00%
Plant in Service	$ 121,769
Construction Work in Progress	93
Less Accumulated Depreciation	(70,884)
Plant Net of Accumulated Depreciation	$ 50,978
Transmission Tie
Jointly Owned Utility Plant Interests [Line Items]
Ownership Interest	35.00%
Plant in Service	$ 24,482
Construction Work in Progress	300
Less Accumulated Depreciation	(7,375)
Plant Net of Accumulated Depreciation	$ 17,407
Wygen III Generating Facility
Jointly Owned Utility Plant Interests [Line Items]
Ownership Interest	52.00%
Plant in Service	$ 143,818
Construction Work in Progress	1,051
Less Accumulated Depreciation	(29,634)
Plant Net of Accumulated Depreciation	$ 115,235
Wygen I Generating Facility
Jointly Owned Utility Plant Interests [Line Items]
Ownership Interest	76.50%
Plant in Service	$ 114,811
Construction Work in Progress	1,579
Less Accumulated Depreciation	(56,553)
Plant Net of Accumulated Depreciation	$ 59,837

The period end amount owned by the reporting utility of a jointly owned utility plant in service.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 10.C)
-URI https://asc.fasb.org/extlink&oid=122136288&loc=d3e659983-123033

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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.

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- Definition

The total period end amount of plant in service and construction in progress net of accumulated depreciation for the utility's share of jointly owned electricity generation plant.

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- Definition

The period end amount of construction work in progress at a jointly owned electricity generation plant.

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- Definition

The period end amount of accumulated depreciation in a jointly owned electricity generation plant.

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- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

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