Note 4 - Loans and Allowance for Loan Losses (Details) - Risk Category of Commercial Loans by Class of Loans - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	$ 585,845	$ 585,752
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	169,360	169,312
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	71,117	73,458
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Owner Occupied [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	61,731	62,287
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Owner Occupied [Member] | Criticized [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	5,548	6,738
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Owner Occupied [Member] | Classified [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	3,838	4,433
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Nonowner Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	71,731	72,002
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Nonowner Occupied [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	61,968	61,577
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Nonowner Occupied [Member] | Criticized [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	1,775	6,305
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Nonowner Occupied [Member] | Classified [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	7,988	4,120
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	26,512	23,852
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	25,375	23,080
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Classified [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	1,137	772
Commercial and Industrial Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	81,034	81,936
Commercial and Industrial Portfolio Segment [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	69,708	70,852
Commercial and Industrial Portfolio Segment [Member] | Criticized [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	4,809	5,232
Commercial and Industrial Portfolio Segment [Member] | Classified [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	6,517	5,852
Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	250,394	251,248
Commercial Portfolio Segment [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	218,782	217,796
Commercial Portfolio Segment [Member] | Criticized [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	12,132	18,275
Commercial Portfolio Segment [Member] | Classified [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans receivable	$ 19,480	$ 15,177