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Note 12 - Segments (Details Textual) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Number of Industry in which Entity Operates | 1 |
Number of Operating Segments | 3 |
Number of Reportable Segments | 3 |
Revenue from Contract with Customer, Excluding Assessed Tax, Total | $ 492,412 | $ 548,184
Asia [Member] |  |
Revenue from Contract with Customer, Excluding Assessed Tax, Total | $ 154,746 | $ 187,203
Assets, Total [Member] | Geographic Concentration Risk [Member] | Asia [Member] |  |
Concentration Risk, Percentage | 30.50% |
Revenue Benchmark [Member] | Customer Concentration Risk [Member] |  |
Concentration Risk, Percentage | 10.20% | 12.30%
Number of Customers | 1 | 1
Revenue from Contract with Customer, Excluding Assessed Tax, Total | $ 50,200 | $ 67,700

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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13531-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13537-108611 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592 + Details
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