Pro Rata Distribution rate of Knife River shares.

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Number of shares retained in Knife River

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Percentage of shares retained in Knife River

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Disposal Group, Including Discontinued Operation, Stock Split, Conversion Ratio

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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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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(4))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

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Amount of operating expense for purchased power of regulated operation.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(2)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

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Basis of Presentation (Details) $ in Thousands, shares in Millions			12 Months Ended
	Oct. 31, 2024	May 31, 2023 shares	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Electric fuel and purchased power			$ 141,148	$ 134,779	$ 119,405
Operation and maintenance			$ (414,491)	(407,081)	(379,951)
Revision of Prior Period, Error Correction, Adjustment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Electric fuel and purchased power				26,900	27,400
Operation and maintenance				$ 26,900	$ 27,400
Discontinued Operations, Disposed of by Means Other than Sale, Spinoff \| Knife River Corporation
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Pro rata distribution of shares, percentage		0.90
Stock split, conversion ratio		0.25
Retained ownership percentage		0.10
Number of retained shares (in shares) \| shares		5.7
Discontinued Operations, Disposed of by Means Other than Sale, Spinoff \| Everus
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Stock split, conversion ratio	0.25