Note 13 - Income Taxes - Effective Income Tax Rate Reconciliation (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Income tax expense at U.S. federal statutory rate	$ 21,343,000	$ 1,505,000	$ 17,810,000	$ 2,735,000
Limited tax benefit due to stock-based compensation	1,930,000	28,000	5,536,000	(81,000)
State deferred income taxes	848,000	0	724,000	0
Other, net	(49,000)	(113,000)	(310,000)	(119,000)
Total income tax expense (benefit)	$ 24,072,000	$ 1,420,000	$ 23,760,000	$ 2,535,000
Effective income tax rate	23.70%	19.80%	28.00%	19.50%