Environmental Matters - Environmental Sites $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
	Jan. 31, 2017 USD ($)	Sep. 30, 2023 USD ($) property party	Sep. 30, 2023 USD ($) party property	Dec. 31, 2022 USD ($)	Sep. 30, 2022 USD ($)
Site Contingency [Line Items]
Current Liabilities		$ 31,923	$ 31,923	$ 28,902	$ 16,554
Non-Current Liabilities		84,602	84,602	89,905	83,276
Gasco/Siltronic Sediments
Site Contingency [Line Items]
Current Liabilities		18,679	18,679	9,744	5,556
Non-Current Liabilities		41,392	41,392	42,120	40,740
Site Contingency, Environmental Remediation Costs Recognized		60,100	60,100
Accrual for Environmental Loss Contingencies, Period Increase (Decrease)		10,100
Gasco/Siltronic Sediments | Minimum [Member]
Site Contingency [Line Items]
Environmental Exit Costs, Anticipated Cost			60,100
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		3,524	3,524	2,634	2,430
Non-Current Liabilities		$ 9,580	$ 9,580	11,270	8,135
Gasco Uplands [Member]
Site Contingency [Line Items]
Site contingency: number of management pieces		2	2
Gasco/Siltronic Upland [Member]
Site Contingency [Line Items]
Current Liabilities		$ 8,908	$ 8,908	16,067	8,367
Non-Current Liabilities		32,512	32,512	35,457	33,354
Front Street [Member]
Site Contingency [Line Items]
Current Liabilities		812	812	457	201
Non-Current Liabilities		939	939	879	868
Additional studies and design costs			1,800
Oregon Steel Mills [Member]
Site Contingency [Line Items]
Current Liabilities		0	0	0	0
Non-Current Liabilities		$ 179	$ 179	$ 179	$ 179
Portland Harbor [Member]
Site Contingency [Line Items]
Number of potentially responsible parties (more than) | party		100	100
EPA final feasibility study and proposed remediation plan, clean-up costs, portland harbor	$ 1,050,000
Number of remediation projects | property		2	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	29
NRD liability claim yakama nation		$ 300	$ 300
Number of Amended Complaints Filed			2