Percentage of shares retained in Knife River

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-3

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Income Taxes - Narrative (Details) $ in Thousands	Dec. 31, 2023 USD ($)	May 31, 2023	Dec. 31, 2022 USD ($)
Discontinued Operations, Disposed of by Means Other than Sale, Spinoff \| Knife River Corporation
Carryforwards [Line Items]
Retained ownership percentage		0.10
State and local jurisdiction
Carryforwards [Line Items]
Operating loss carryforwards	$ 816		$ 785
Tax credit carryforward, amount	$ 33,700		$ 35,100