Note 17 - Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Balance	$ 640,093	$ 522,007
Balance	773,491	640,093
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Balance	(1,638)	(1,364)
Other comprehensive income (loss) before reclassifications	1,977	(549)
Amounts reclassified from accumulated other comprehensive income (loss)	(1)	66
Tax effect	(203)	209
Net current period other comprehensive income (loss)	1,773	(274)
Balance	135	(1,638)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Balance	(3,905)	3,177
Other comprehensive income (loss) before reclassifications	(1,706)	(7,082)
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Tax effect	0	0
Net current period other comprehensive income (loss)	(1,706)	(7,082)
Balance	(5,611)	(3,905)
AOCI Attributable to Parent [Member]
Balance	(5,543)	1,813
Other comprehensive income (loss) before reclassifications	271	(7,631)
Amounts reclassified from accumulated other comprehensive income (loss)	(1)	66
Tax effect	(203)	209
Net current period other comprehensive income (loss)	67	(7,356)
Balance	$ (5,476)	$ (5,543)