Note 9 - Fair Values - Fair Value of Assets Measured on a Non-recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Other real estate owned	$ 34	$ 31
Fair Value, Nonrecurring [Member]
Other real estate owned	34	31
Total assets measured at fair value	34	31
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 1 [Member]
Other real estate owned
Total assets measured at fair value
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 2 [Member]
Other real estate owned
Total assets measured at fair value
Fair Value, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Other real estate owned	34	31
Total assets measured at fair value	$ 34	$ 31