Note 12 - Segments (Details Textual) $ in Thousands		12 Months Ended
Oct. 01, 2019	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Number of Industry in which Entity Operates		1
Number of Operating Segments	3	3
Number of Reportable Segments		3
Revenue from Contract with Customer, Excluding Assessed Tax, Total		$ 465,771	$ 492,412
Asia [Member]
Revenue from Contract with Customer, Excluding Assessed Tax, Total		$ 129,303	$ 154,746
Assets, Total [Member] \| Geographic Concentration Risk [Member] \| Asia [Member]
Concentration Risk, Percentage		32.60%
Revenue Benchmark [Member] \| Customer Concentration Risk [Member]
Concentration Risk, Percentage		11.90%	10.20%
Number of Customers		1	1
Revenue from Contract with Customer, Excluding Assessed Tax, Total		$ 55,200	$ 50,200

The number of customers.

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

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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.

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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.

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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.

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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.

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