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Environmental Matters - Environmental Sites $ in Thousands	1 Months Ended	6 Months Ended
Environmental Matters - Environmental Sites $ in Thousands	Jan. 31, 2017 USD ($)	Jun. 30, 2024 USD ($) party property	Dec. 31, 2023 USD ($)	Jun. 30, 2023 USD ($)
Site Contingency [Line Items]
Current Liabilities		$ 25,456	$ 32,454	$ 22,878
Non-Current Liabilities		83,794	89,173	86,897
Gasco/Siltronic Sediments
Site Contingency [Line Items]
Current Liabilities		9,654	12,428	8,103
Non-Current Liabilities		40,665	42,550	42,120
Site Contingency, Environmental Remediation Costs Recognized		50,300
Gasco/Siltronic Sediments \| Minimum [Member]
Site Contingency [Line Items]
Environmental Exit Costs, Anticipated Cost		50,300
Gasco/Siltronic Sediments \| Maximum [Member]
Site Contingency [Line Items]
Environmental Exit Costs, Anticipated Cost		350,000
Portland Harbor Other [Member]
Site Contingency [Line Items]
Current Liabilities		3,218	3,035	2,838
Non-Current Liabilities		$ 10,143	11,270	10,143
Gasco Uplands [Member]
Site Contingency [Line Items]
Site contingency: number of management pieces		2
Gasco/Siltronic Upland [Member]
Site Contingency [Line Items]
Current Liabilities		$ 11,822	16,304	11,424
Non-Current Liabilities		32,379	34,235	33,516
Front Street [Member]
Site Contingency [Line Items]
Current Liabilities		762	687	513
Non-Current Liabilities		428	939	939
Additional studies and design costs		1,200
Oregon Steel Mills [Member]
Site Contingency [Line Items]
Current Liabilities		0	0	0
Non-Current Liabilities		$ 179	$ 179	$ 179
Portland Harbor [Member]
Site Contingency [Line Items]
Number of potentially responsible parties (more than) \| party		100
EPA final feasibility study and proposed remediation plan, clean-up costs, portland harbor	$ 1,050,000
Number of remediation projects \| property		2
Portland Harbor [Member] \| Minimum [Member]
Site Contingency [Line Items]
Percentage of clean-up costs	(30.00%)
Portland Harbor [Member] \| Maximum [Member]
Site Contingency [Line Items]
Percentage of clean-up costs	50.00%
Yakama Nation [Member] \| Portland Harbor Other [Member]
Site Contingency [Line Items]
Trustee Council Members - Number of Claimants		1
Site Contingency, Number of Other Third-Party Defendants		29
NRD liability claim yakama nation		$ 300
Number of Amended Complaints Filed		2