Note 17 - Employee Benefit Plans - (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	4.00%
Employee Compensation and Benefits	$ 967,000	$ 690,000	$ 542,000
Deferred Compensation Arrangement with Individual, Recorded Liability	2,500,000	2,400,000
Deferred Compensation Arrangement with Individual, Compensation Expense	$ 256,000	$ 224,000	$ 209,000