Note 16 - Income Taxes (Details Textual) - USD ($) $ in Thousands		12 Months Ended
	Dec. 22, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	35.00%		35.00%	35.00%	35.00%
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	$ (2,300)
Operating Loss Carryforwards			$ 4,000
Unrecognized Tax Benefits			0	$ 0
Income Tax Expense (Benefit)			14,386	18,323	$ 17,496
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation				$ 647	$ 847
Accounting Standards Update 2016-09 [Member]
Income Tax Expense (Benefit)			$ (400)
Domestic Tax Authority [Member] | Earliest Tax Year [Member]
Open Tax Year			2014
Domestic Tax Authority [Member] | Latest Tax Year [Member]
Open Tax Year			2016
Foreign Tax Authority [Member] | Earliest Tax Year [Member]
Open Tax Year			2011
Foreign Tax Authority [Member] | Latest Tax Year [Member]
Open Tax Year			2016
Scenario, Forecast [Member]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent		21.00%