Note 18 - Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Balance	$ 522,007	$ 431,116
Balance	640,093	522,007
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Balance	(1,364)	(1,023)
Other comprehensive income (loss) before reclassifications	(549)	(343)
Amounts reclassified from accumulated other comprehensive income (loss)	66	2
Net current period other comprehensive income (loss)	(274)	(341)
Tax effect	209
Balance	(1,638)	(1,364)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Balance	3,177	(3,192)
Other comprehensive income (loss) before reclassifications	(7,082)	6,369
Net current period other comprehensive income (loss)	(7,082)	6,369
Balance	(3,905)	3,177
AOCI Attributable to Parent [Member]
Balance	1,813	(4,215)
Other comprehensive income (loss) before reclassifications	(7,631)	6,026
Amounts reclassified from accumulated other comprehensive income (loss)	66	2
Net current period other comprehensive income (loss)	(7,356)	6,028
Tax effect	209
Balance	$ (5,543)	$ 1,813