Note 15 - Fair Value Measurements - Assets Measured At Fair Value On a Non-recurring Basis and Quantitative Information (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Recorded investment $ 5,604 $ 7,961
Related allowance 302 381
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Market Approach Valuation Technique [Member] | Impaired Loans, Collateral Dependent [Member]    
Recorded investment 482 718
Related allowance 68 124
Fair Value $ 414 $ 594
Selling Cost 10.00% 10.00%
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Market Approach Valuation Technique [Member] | Impaired Loans, Collateral Dependent [Member] | Minimum [Member]    
Selling Cost 10.00% 10.00%
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Market Approach Valuation Technique [Member] | Impaired Loans, Collateral Dependent [Member] | Maximum [Member]    
Selling Cost 10.00% 10.00%
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Market Approach Valuation Technique [Member] | Other Real Estate Owned [Member]    
Recorded investment $ 1,949 $ 3,104
Related allowance
Fair Value $ 1,949 $ 3,104
Selling Cost 10.00% 10.00%
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Market Approach Valuation Technique [Member] | Other Real Estate Owned [Member] | Minimum [Member]    
Selling Cost 10.00% 10.00%
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Market Approach Valuation Technique [Member] | Other Real Estate Owned [Member] | Maximum [Member]    
Selling Cost 10.00% 10.00%
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Income Approach Valuation Technique [Member] | Impaired Loans, Other [Member]    
Recorded investment $ 3,247 $ 3,757
Related allowance 234 257
Fair Value $ 3,013 $ 3,500
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Income Approach Valuation Technique [Member] | Impaired Loans, Other [Member] | Minimum [Member]    
Discount Rate 3.00% 2.90%
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Income Approach Valuation Technique [Member] | Impaired Loans, Other [Member] | Maximum [Member]    
Discount Rate 7.50% 7.50%