Note 10 - Accumulated Other Comprehensive Income (Loss) - Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Balance	$ 831,977	$ 601,249	$ 644,356	$ 585,790
Balance	824,621	625,821	824,621	625,821
AOCI Attributable to Parent [Member]
Balance	(8,115)	(9,634)	(3,420)	(7,018)
Balance	(13,458)	(6,524)	(13,458)	(6,524)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Other comprehensive income (loss) before reclassifications	(5,298)	3,110	(10,110)	494
Amounts reclassified from accumulated other comprehensive loss	0	0	0	0
Net current-period other comprehensive income (loss)	(5,298)	3,110	(10,110)	494
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Other comprehensive income (loss) before reclassifications	(45)	0	72	0
Amounts reclassified from accumulated other comprehensive loss	0	0	0	0
Net current-period other comprehensive income (loss)	$ (45)	$ 0	$ 72	$ 0