Note 15 - Accumulated Other Comprehensive Loss - Other Comprehensive Loss (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Balance	$ 541,497	$ 461,215	$ 379,833
Balance	585,790	541,497	461,215
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Balance	(8,492)	(5,234)	(10,753)
Other comprehensive (loss) income before reclassifications	1,474	(3,258)	5,519
Amounts reclassified from accumulated other comprehensive income (loss)	0	0	0
Net current-period other comprehensive (loss) income	1,474	(3,258)	5,519
Balance	$ (7,018)	$ (8,492)	$ (5,234)

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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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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