Note 11 - Assets and Liabilities Measured and Reported at Fair Value - Significant Unobservable Inputs (Details) - Fair Value, Inputs, Level 3 [Member] - Appraisal Discount Method [Member] - Impaired Loans [Member] $ in Thousands	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Impaired loans - collateral dependent, fair value	$ 778	$ 7,253
Other real estate owned	493	493
Impaired loans - collateral dependent, fair value	$ 778	$ 7,253
Weighted Average [Member]
Impaired loans - collateral dependent, weighted average of input	0.145	0.603
Other Real Estate Owned, Measurement Input	0.171	0.171
Impaired Loans, Measurement Input	0.145	0.603