Note 10 - Accumulated Other Comprehensive Loss - Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Balance	$ 542,795	$ 487,676	$ 541,497	$ 461,215
Balance	558,113	506,253	558,113	506,253
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Balance	(8,016)	(2,841)	(8,492)	(5,234)
Other comprehensive income (loss) before reclassifications	(478)	(3,518)	(2)	(1,125)
Amounts reclassified from accumulated other comprehensive loss	0	0	0	0
Net current-period other comprehensive income (loss)	(478)	(3,518)	(2)	(1,125)
Balance	$ (8,494)	$ (6,359)	$ (8,494)	$ (6,359)

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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