Note 2 - Schedule of Adoption of New Revenue Standard Impacted the Consolidated Financial Statements - Balance Sheet (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Trade receivables, net	$ 55,166		$ 75,144
Contract assets	88,990
Inventories, net	104,544		138,542
Contract liabilities, current	6,721
Taxes payable	8,162		43
Retained earnings	470,103		$ 429,826
Accounting Standards Updated 2014-09 [Member] \| Effect of Change Higher/(Lower) [Member]
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Contract assets	88,990
Inventories, net	(51,886)
Taxes payable	7,819
Retained earnings	29,629	$ 16,219
Accounting Standards Updated 2014-09 [Member] \| Amount Without Adoption of ASC 606 [Member]
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Trade receivables, net	55,166
Inventories, net	156,430
Contract liabilities, current	6,721
Taxes payable	343
Retained earnings	$ 440,474

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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