Note 18 - Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Loss by Component (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018
Balance		$ 176,470	$ 157,960
Other comprehensive income (loss):		1,236	(5,213)
Balance		168,051	176,470
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Balance		(22,635)	(16,537)
Other comprehensive income (loss) before reclassifications		2,603	(6,098)
Amounts reclassified from accumulated other comprehensive income (loss)
Other comprehensive income (loss):		2,603	(6,098)
Effect of adoption of ASU 2018-02 (Topic 220)
Balance		(20,032)	(22,635)
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Balance		12	145
Other comprehensive income (loss) before reclassifications			37
Amounts reclassified from accumulated other comprehensive income (loss)			(170)
Other comprehensive income (loss):			(133)
Effect of adoption of ASU 2018-02 (Topic 220)
Balance		12	12
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Balance		(2,215)	(3,233)
Other comprehensive income (loss) before reclassifications		(1,492)	679
Amounts reclassified from accumulated other comprehensive income (loss)	[1]	125	339
Other comprehensive income (loss):		(1,830)	1,018
Effect of adoption of ASU 2018-02 (Topic 220)		(463)
Balance		(4,045)	(2,215)
AOCI Attributable to Parent [Member]
Balance		(24,838)	(19,625)
Other comprehensive income (loss) before reclassifications		1,111	(5,382)
Amounts reclassified from accumulated other comprehensive income (loss)		125	169
Other comprehensive income (loss):		773	(5,213)
Effect of adoption of ASU 2018-02 (Topic 220)		(463)
Balance		$ (24,065)	$ (24,838)

[1] This reclassification relates to the amortization of prior service costs and gains/losses associated with the Company's SERP plan. This expense is allocated between cost of sales and selling, general and administrative expense based upon the employment classification of the plan participants.