Note 15 - Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Income (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Balance	$ 640,093
Balance	680,251
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Balance	(1,638)
Other comprehensive income before reclassifications	924
Tax effect	(98)
Net current period other comprehensive income	826
Balance	(812)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Balance	(3,905)
Other comprehensive income before reclassifications	3,677
Net current period other comprehensive income	3,677
Balance	(228)
AOCI Attributable to Parent [Member]
Balance	(5,543)
Other comprehensive income before reclassifications	4,601
Tax effect	(98)
Net current period other comprehensive income	4,503
Balance	$ (1,040)

Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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