Note 9 - Income Taxes - Reconciliation of Taxes on Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Tax provision computed at the federal statutory rate, amount	$ 2,549	$ (1,534)
Tax provision computed at the federal statutory rate, percent	21.00%	21.00%
Different tax rates applicable to foreign operations, amount	$ 311	$ 2,978
Different tax rates applicable to foreign operations, percent	3.00%	(41.00%)
(Reversal of) increase in liability for uncertain tax positions - net	$ (1,432)	$ 320
Increase in (reversal of) liability for uncertain tax positions - net, percent	(12.00%)	(4.00%)
Impact of U.S. Tax Reform, amount	$ (1,129)	$ 0
Impact of U.S. Tax Reform, percent	(9.00%)	0.00%
Research and experimentation and foreign tax credits	$ (245)	$ (907)
Research and experimentation and foreign tax credits	(2.00%)	12.00%
State taxes, net of federal benefit, amount	$ 4	$ (54)
State taxes, net of federal benefit, percent	0.00%	1.00%
SERP/COLI and restricted stock income	$ (234)	$ (547)
SERP/COLI and restricted stock income, percent	(2.00%)	7.00%
Impairment of goodwill	$ 0	$ 1,522
Impairment of goodwill, percent	0.00%	(21.00%)
Other, net	$ (483)	$ (337)
Other, net, percent	(4.00%)	5.00%
Income Tax Expense (Benefit), Total	$ (659)	$ 1,441
Tax (benefit) provision computed at the Company's effective tax rate	(5.00%)	(20.00%)

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