Note 5 - Income Taxes - Components of Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Current:
Federal	$ 33,416	$ 18,025	$ 18,872
State	4,706	3,914	3,367
Total current	38,122	21,939	22,239
Deferred:
Federal	(13,526)	9,795	3,462
State	(1,053)	2,083	603
Total deferred	(14,579)	11,878	4,065
Total expense	$ 23,543	$ 33,817	$ 26,304