Note 7 - Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Income tax expense (benefit)	$ 7,872	$ 8,748	$ 11,404	$ 14,534
Effective income tax rate reconciliation, percent	33.40%	17.60%	30.30%	18.30%
Effective income tax rate excluding the impact of any proforma items, Percent	25.90%		25.40%