Note 13 - Income Taxes - Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income taxes at the federal statutory rate	$ 31,862	$ 39,530	$ 38,469
State income taxes, net of federal benefit	4,487	5,303	4,913
Tax effect of permanent differences	283	1,562	596
Foreign tax rate differential	(111)	0	0
Other, net	315	1,545	129
Provision (benefit) for income taxes	$ 36,836	$ 47,940	$ 44,107

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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