Note 12 - Federal and State Income Taxes - Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current:
Federal									$ (56)	$ (48)	$ (79)
State									646	189	441
Total current income tax provision									590	141	362
Deferred:
Federal									2,177	6,185	(24,622)
State									(552)	1,021	(8)
Total deferred income tax provision (benefit)									1,625	7,206	(24,630)
Total income tax provision (benefit) expense	$ (4,168)	$ 1,264	$ 2,301	$ 2,818	$ 1,883	$ 3,129	$ 2,005	$ 330	$ 2,215	$ 7,347	$ (24,268)