Note 9 - Benefit Plans (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Deferred Compensation Liability, Current and Noncurrent, Total	$ 2,000	$ 3,200
Profit Sharing Plan [Member]
Defined Contribution Plan, Employer Discretionary Contribution Amount	0	0
Pension Plan [Member]
Defined Contribution Plan, Employer Discretionary Contribution Amount	305	298
Supplemental Executive Retirement Plan [Member]
Retirement Plan, Annual, Accrued Unfunded Contributions	173	108
Liability, Other Retirement Benefits	$ 657	$ 557