Note 12 - Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Loss by Component (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Balance		$ 186,323	$ 161,832	$ 185,799	$ 168,051
Other comprehensive income (loss)		2,640	742	209	(1,437)
Balance		196,598	167,928	196,598	167,928
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Balance				(13,142)
Other comprehensive income (loss) before reclassifications				11
Amount reclassified from accumulated other comprehensive income (loss)				0
Other comprehensive income (loss)				11
Balance		(13,131)		(13,131)
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Balance				19
Other comprehensive income (loss) before reclassifications				(1)
Amount reclassified from accumulated other comprehensive income (loss)				0
Other comprehensive income (loss)				(1)
Balance		18		18
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Balance				(4,940)
Other comprehensive income (loss) before reclassifications				0
Amount reclassified from accumulated other comprehensive income (loss)	[1]			199
Other comprehensive income (loss)				199
Balance		(4,741)		(4,741)
AOCI Attributable to Parent [Member]
Balance		(20,494)	(26,244)	(18,063)	(24,065)
Other comprehensive income (loss) before reclassifications				10
Amount reclassified from accumulated other comprehensive income (loss)				199
Other comprehensive income (loss)				209
Balance		$ (17,854)	$ (25,502)	$ (17,854)	$ (25,502)

[1] This reclassification relates to the amortization of prior service costs and gains/losses associated with the Company's SERP Plan. This expense is reflected in other income (expense), net on the accompanying condensed consolidated statement of operations.