Note 15 - Accumulated Other Comprehensive Income (Loss) - Other Comprehensive Loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Balance at beginning of period	$ 644,356	$ 585,790	$ 541,497
Balance at end of period	828,493	644,356	585,790
AOCI Attributable to Parent [Member]
Balance at beginning of period	(3,420)	(7,018)	(8,492)
Balance at end of period	(16,817)	(3,420)	(7,018)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Other comprehensive (loss) income before reclassifications	(13,278)	3,598	1,474
Net current-period other comprehensive (loss) income	(13,278)	3,598	1,474
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Other comprehensive (loss) income before reclassifications	(119)	0	0
Net current-period other comprehensive (loss) income	$ (119)	$ 0	$ 0