Note 9 - Accumulated Other Comprehensive Loss - Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Balance	$ 587,740	$ 542,795	$ 585,790	$ 541,497
Balance	601,249	558,113	601,249	558,113
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Balance	(9,998)	(8,016)	(7,018)	(8,492)
Other comprehensive income (loss) before reclassifications	364	(478)	(2,616)	(2)
Amounts reclassified from accumulated other comprehensive loss	0	0	0	0
Net current-period other comprehensive income (loss)	364	(478)	(2,616)	(2)
Balance	$ (9,634)	$ (8,494)	$ (9,634)	$ (8,494)

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

- Definition

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.

+ References + Details