Note 12 - Segments (Details Textual) $ in Thousands	12 Months Ended
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

The number of customers.

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- Definition

Number of industry in which entity operates with its reportable operating segments.

+ References

No definition available.

+ Details

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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
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-Name Accounting Standards Codification
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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

No definition available.

+ Details

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-Publisher FASB
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