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Note 15 - Commitments and Contingencies (Details Textual) $ in Millions | 1 Months Ended |  |
--- | --- | --- | ---
Jan. 31, 2017 USD ($) | Jul. 31, 2014 USD ($) | Dec. 31, 2017 USD ($) | Jun. 30, 2014 USD ($)
Number Of Potentially Responsible Parties |  |  | 100 |
Estimated Cost of EPA Selected Remedy | $ 1,000.0 |  |  |
Estimated Time to Complete Selected EPA Remedy | 13 years |  |  |
Letters of Credit Outstanding, Amount |  |  | $ 2.0 |
Portland Harbor Natural Resources Trustee Council [Member] |  |  |  |
Loss Contingency, Accrual, Current |  |  |  | $ 0.4
Loss Contingency Accrual, Payments |  | $ 0.2 |  |
Lower Willamette Group [Member] |  |  |  |
Number Of Potentially Responsible Parties |  |  | 14 |

X
- Definition The estimated cost of the remedy selected by EPA. + References No definition available. + Details
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X
- Definition The estimated amount of time to complete the selected EPA remedy. + References No definition available. + Details
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- Definition Number of potentially responsible parties for Portland Harbor Superfund site. + References No definition available. + Details
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- Definition Amount of loss contingency liability expected to be resolved within one year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349 + Details
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- Definition Amount of cash outflow reducing loss contingency liability. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349 + Details
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