Note 7 - Income Taxes - Income Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Expected federal income taxes	$ 8,392	$ 8,991	$ 10,210
Foreign tax rate differential	(4)	(24)	26
State income taxes, net of federal benefit and state tax credits	1,323	2,100	1,531
Share-based compensation	(334)	(120)	(660)
Federal tax credits	(569)	(408)	(272)
Uncertain tax positions	73	22	254
Reclassification of cumulative translation adjustment into earnings	0	539	0
Withholding tax on repatriation of foreign earnings	0	(100)	8
Non-deductible expenses	92	30	0
Other	18	(15)	58
Income Tax Expense (Benefit)	$ 8,991	$ 11,015	$ 11,155

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The sum of the differences between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable uncertain tax positions.

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

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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