Note 9 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Unrecognized Tax Benefits, Ending Balance		$ 28,516	$ 29,061	$ 28,951
Liability for Uncertainty in Income Taxes, Current		2,400	2,200
Liability for Uncertainty in Income Taxes, Noncurrent		26,089	26,901
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense, Total		800	700
Income Tax Expense (Benefit) on Reversal of Interest and Penalties		500	700
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total		5,200	4,900
Income (Loss) from Continuing Operations before Income Taxes, Domestic		(6,000)	(17,100)
Income (Loss) from Continuing Operations before Income Taxes, Foreign		18,100	9,800
Deferred Tax Assets, Gross, Total		22,937	23,335
Deferred Tax Assets, Operating Loss Carryforwards, Total		7,744	8,042
Tax Credit Carryforward, Amount		2,600
Deferred Tax Assets, Tax Credit Carryforwards, Total		600
Deferred Tax Assets, Valuation Allowance, Total		6,289	$ 8,216
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount		200
Federal and State and Local Authority [Member]
Operating Loss Carryforwards, Total		27,500
Deferred Tax Assets, Operating Loss Carryforwards, Total		$ 5,900
Forecast [Member]
Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations	$ 2,400