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Note 8 - Commitments and Contingencies (Details Textual) $ in Millions | 1 Months Ended |  |  |
--- | --- | --- | --- | ---
Jan. 31, 2017 USD ($) | Sep. 30, 2025 USD ($) | Nov. 30, 2024 | Jun. 30, 2014 USD ($)
Letters of Credit Outstanding, Amount |  | $ 1.6 |  |
Capital Addition Purchase Commitments [Member] |  |  |  |
Other Commitment |  | $ 2.1 |  |
Portland Harbor Natural Resources Trustee Council [Member] |  |  |  |
Loss Contingency, Accrual, Current |  |  |  | $ 0.4
Portland Harbor Superfund Site [Member] |  |  |  |
Number Of Potentially Responsible Parties | 150 |  | 60 |
Estimated Cost of EPA Selected Remedy | $ 1,000.0 |  |  |
Estimated Time to Complete Selected EPA Remedy (Year) | 13 years |  |  |
Lower Willamette Group [Member] |  |  |  |
Number Of Potentially Responsible Parties | 14 |  |  |

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- Definition Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 942 -SubTopic 235 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477314/942-235-S99-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480738/235-10-S50-4 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3 + Details
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