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Note 14 - Commitments and Contingencies (Details Textual) $ in Thousands | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jan. 31, 2015 USD ($) | Jul. 31, 2014 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Jun. 30, 2014 USD ($)
Estimated Cost of EPA Selected Remedy |  |  | $ 1,050,000 |  |
Estimated Time to Complete Selected EPA Remedy |  |  | 13 years |  |
Number Of Potentially Responsible Parties |  |  | 100 |  |
Insurance Recoveries | $ 2,600 |  |  |  |
Estimated Litigation Liability, Current |  |  | $ 1,750 |  |
Letters of Credit Outstanding, Amount |  |  | 2,000 |  |
Pending Litigation [Member] |  |  |  |  |
Estimated Litigation Liability, Current |  |  | 1,800 |  |
Portland Harbor Natural Resources Trustee Council [Member] |  |  |  |  |
Loss Contingency, Accrual, Current |  |  |  |  | $ 400
Loss Contingency Accrual, Payments |  | $ 200 |  |  |
Voluntary Cleanup Program [Member] | Estimated [Member] |  |  |  |  |
Accrual for Environmental Loss Contingencies |  |  | 200 |  |
Voluntary Cleanup Program [Member] | Minimum [Member] |  |  |  |  |
Loss Contingency, Estimate of Possible Loss |  |  | 100 |  |
Voluntary Cleanup Program [Member] | Maximum [Member] |  |  |  |  |
Loss Contingency, Estimate of Possible Loss |  |  | $ 1,700 |  |

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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + 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=25496072&loc=d3e14326-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346 + Details
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