Note 15 - Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019
Balance	$ 704,154		$ 640,093
Balance	734,428	$ 704,154
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Balance	(201)	(812)	(1,638)
Other comprehensive income before reclassifications	272	675	924
Tax effect	(38)	(64)	(98)
Other comprehensive income	234	611	826
Balance	33	(201)	(812)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Balance	(3,937)	(228)	(3,905)
Other comprehensive income before reclassifications	(6,135)	(3,709)	3,677
Other comprehensive income	(6,135)	(3,709)	3,677
Balance	(10,072)	(3,937)	(228)
AOCI Attributable to Parent [Member]
Balance	(4,138)	(1,040)	(5,543)
Other comprehensive income before reclassifications	(5,863)	(3,034)	4,601
Tax effect	(38)	(64)	(98)
Other comprehensive income	(5,901)	(3,098)	4,503
Balance	$ (10,039)	$ (4,138)	$ (1,040)