Environmental Matters - Environmental Sites $ in Thousands	1 Months Ended	3 Months Ended
	Jan. 31, 2017 USD ($)	Mar. 31, 2022 USD ($) property party	Dec. 31, 2021 USD ($)	Mar. 31, 2021 USD ($)
Site Contingency [Line Items]
Current Liabilities		$ 22,286	$ 26,985	$ 23,594
Non-Current Liabilities		86,830	88,851	89,941
Gasco/Siltronic Sediments
Site Contingency [Line Items]
Current Liabilities		6,086	7,582	7,026
Non-Current Liabilities		41,408	42,076	42,374
Site Contingency, Environmental Remediation Costs Recognized		47,500
Gasco/Siltronic Sediments | Minimum [Member]
Site Contingency [Line Items]
Environmental Exit Costs, Anticipated Cost		47,500
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		2,198	2,592	2,175
Non-Current Liabilities		$ 9,092	9,570	6,954
Gasco Uplands [Member]
Site Contingency [Line Items]
Site contingency: number of management pieces		2
Gasco/Siltronic Upland [Member]
Site Contingency [Line Items]
Current Liabilities		$ 13,203	15,711	13,135
Non-Current Liabilities		35,283	36,215	39,302
Front Street [Member]
Site Contingency [Line Items]
Current Liabilities		799	1,100	1,258
Non-Current Liabilities		868	811	1,132
Additional studies and design costs		1,700
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