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v3.23.1

Subsequent Events (Details 3) - Subsequent Event [Member] | May 03, 2023
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Subsequent Events [Line Items] |
Percent of Shares, Retained, in conjunction with spin off | 10.00%
Knife River Holding Company |
Subsequent Events [Line Items] |
Percent of Shares Distributed in conjunction with spin off | 90.00%

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- Definition Percent of Shares Distributed in conjunction with spin off + References No definition available. + Details
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- Definition Percent of Shares, Retained, in conjunction with spin off + References No definition available. + Details
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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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 830 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481674/830-30-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 855 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483399/855-10-50-2 + Details
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- Details
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- Details
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