Note 13 - Fair Value - Assets Measured at Fair Value on Nonrecurring Basis (Details) - Fair Value, Measurements, Nonrecurring [Member] - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Impaired Loans [Member] | Non-covered Loans [Member]
Total Fair Value	$ 4,954	$ 5,015
Impaired Loans [Member] | Non-covered Loans [Member] | Fair Value, Inputs, Level 1 [Member]
Total Fair Value
Impaired Loans [Member] | Non-covered Loans [Member] | Fair Value, Inputs, Level 2 [Member]
Total Fair Value
Impaired Loans [Member] | Non-covered Loans [Member] | Fair Value, Inputs, Level 3 [Member]
Total Fair Value	4,954	5,015
OREO [Member] | Non-covered Loans [Member]
Total Fair Value	3,032	2,359
OREO [Member] | Non-covered Loans [Member] | Fair Value, Inputs, Level 1 [Member]
Total Fair Value
OREO [Member] | Non-covered Loans [Member] | Fair Value, Inputs, Level 2 [Member]
Total Fair Value
OREO [Member] | Non-covered Loans [Member] | Fair Value, Inputs, Level 3 [Member]
Total Fair Value	3,032	2,359
OREO [Member] | Covered Loans [Member]
Total Fair Value	59	105
OREO [Member] | Covered Loans [Member] | Fair Value, Inputs, Level 1 [Member]
Total Fair Value
OREO [Member] | Covered Loans [Member] | Fair Value, Inputs, Level 2 [Member]
Total Fair Value
OREO [Member] | Covered Loans [Member] | Fair Value, Inputs, Level 3 [Member]
Total Fair Value	$ 59	$ 105