Note 6 - Income Taxes - Schedule of Components of Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current:
U.S. Federal	$ (5,933)	$ 15,905	$ 20,634
U.S. State	(2,294)	4,717	3,240
Non-U.S.	514	1,336	1,436
Current Income Tax Expense (Benefit), Total	(7,713)	21,958	25,310
Deferred:
U.S. Federal	10,936	(9,386)	(7,509)
U.S. State	749	(8,033)	(8,973)
Deferred Income Tax Expense (Benefit), Total	11,685	(17,419)	(16,482)
Total Income Tax Expense	$ 3,972	$ 4,539	$ 8,828