Note 14 - Income Taxes - Effective Income Tax Rate (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Loss before taxes of taxable entities	$ (1,349)	$ 1,528	$ (41,222)	$ (18,413)	$ (6,952)	$ (4,778)	$ 2,565	$ (2,651)	$ (59,456)	$ (11,816)	$ (20,305)
Benefit for income taxes at federal statutory rate									12,485	2,481	4,264
Provisional rate adjustment - tax reform									0	0	148
NOL carryback rate differential									9,574	0	0
State income taxes, net of federal benefit									3,980	781	1,396
Tax credits									1,509	1,238	346
Stock compensation									(276)	(389)	(12)
Non-deductible expenses related to Section 162(m)									(48)	(163)	0
Other									(637)	(133)	(67)
Benefit for income taxes									$ 26,587	$ 3,815	$ 6,075
Effective tax rate									44.70%	32.30%	29.90%