Note 14 - Accumulated Other Comprehensive Income - Changes in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2021	Mar. 31, 2021
Balance	$ 1,021,577	$ 966,587
Balance	1,087,355	1,021,577
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Balance	947	1,601
Other comprehensive income (loss) before reclassifications	(169)	(754)
Amounts reclassified from accumulated other comprehensive income		(24)
Tax effect	21	124
Net current period other comprehensive loss	(148)	(654)
Balance	799	947
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Balance	6,065	8,539
Other comprehensive income (loss) before reclassifications	5,437	(2,474)
Amounts reclassified from accumulated other comprehensive income		0
Tax effect	0	0
Net current period other comprehensive loss	5,437	(2,474)
Balance	11,502	6,065
AOCI Attributable to Parent [Member]
Balance	7,012	10,140
Other comprehensive income (loss) before reclassifications	5,268	(3,228)
Amounts reclassified from accumulated other comprehensive income		(24)
Tax effect	21	124
Net current period other comprehensive loss	5,289	(3,128)
Balance	$ 12,301	$ 7,012