Note 8 - Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Tax Expense (Benefit), Total	$ 3,700	$ 871	$ 4,950	$ 1,471
Effective Income Tax Rate Reconciliation, Percent, Total	19.60%	23.80%	21.10%	22.20%
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent				(5.00%)
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Percent				1.80%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent				0.90%
Changes in Uncertain Tax Positions				0.30%