Note 7 - Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Income Tax Expense (Benefit), Total	$ 5,185	$ 1,908
Income Tax Expense (Benefit), Percentage of Earnings Before Income Taxes	16.40%
Effective Income Tax Rate Reconciliation, Percent, Total	44.60%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%