Note 10 - Income Taxes - Income Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Computed "expected" income tax expense	$ 16,643	$ (3,554)
State income taxes, net of federal income tax effect	3,787	(227)
831(b) election	(8)	(123)
Per diem allowances	0	1,028
Tax contingency accruals	(295)	65
Valuation allowance, net	(242)	(139)
Tax credits	(295)	(403)
Excess tax benefits on share-based compensation	(259)	129
Change in prior year estimates	(86)	288
Executive compensation disallowance	1,705	0
Other, net	11	132
Income tax (benefit) expense	$ 20,962	$ (2,804)

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