Note 15 - Disclosures About Fair Value of Assets and Liabilities - Fair Value of Assets Measured on Non-recurring Basis (Details) - Fair Value, Nonrecurring [Member] - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Impaired loans, fair value	$ 1,483	$ 10,428
Foreclosed assets held for sale, fair value	233	909
Fair Value, Inputs, Level 1 [Member]
Impaired loans, fair value
Foreclosed assets held for sale, fair value
Fair Value, Inputs, Level 2 [Member]
Impaired loans, fair value
Foreclosed assets held for sale, fair value
Fair Value, Inputs, Level 3 [Member]
Impaired loans, fair value	1,483	10,428
Foreclosed assets held for sale, fair value	$ 233	$ 909