Note 6 - Loans Receivable and Allowance for Loan Losses - Past Due Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Loans receivable, total past due	$ 21,199	$ 19,987
Loans receivable, current	1,005,200	945,057
Loans receivable	1,026,399	965,044
Loans receivable greater than 90 days and accruing		302
Financing Receivables, 30 to 59 Days Past Due [Member]
Loans receivable, total past due	2,206	1,060
Financing Receivables, 60 to 89 Days Past Due [Member]
Loans receivable, total past due	464	31
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans receivable, total past due	18,529	18,896
Commercial Real Estate Portfolio Segment [Member]
Loans receivable, total past due	12,739	13,098
Loans receivable, current	382,101	365,421
Loans receivable	394,840	378,519
Loans receivable greater than 90 days and accruing
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Loans receivable, total past due
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans receivable, total past due	6	9
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans receivable, total past due	12,733	13,089
Construction and Land Development Portfolio Segment [Member]
Loans receivable, total past due
Loans receivable, current	78,636	61,453
Loans receivable	78,636	61,453
Loans receivable greater than 90 days and accruing
Construction and Land Development Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Loans receivable, total past due
Construction and Land Development Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans receivable, total past due
Construction and Land Development Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans receivable, total past due
Commercial Portfolio Segment [Member]
Loans receivable, total past due	4,742	3,719
Loans receivable, current	184,131	171,025
Loans receivable	188,873	174,744
Loans receivable greater than 90 days and accruing
Commercial Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Loans receivable, total past due	1,009	568
Commercial Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans receivable, total past due	434
Commercial Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans receivable, total past due	3,299	3,151
Owner Occupied Real Estate [Member]
Loans receivable, total past due	2,864	2,186
Loans receivable, current	271,132	274,800
Loans receivable	273,996	276,986
Loans receivable greater than 90 days and accruing		172
Owner Occupied Real Estate [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Loans receivable, total past due	1,174	468
Owner Occupied Real Estate [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans receivable, total past due
Owner Occupied Real Estate [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans receivable, total past due	1,690	1,718
Consumer Portfolio Segment [Member]
Loans receivable, total past due	854	854
Loans receivable, current	66,548	62,806
Loans receivable	67,402	63,660
Loans receivable greater than 90 days and accruing
Consumer Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Loans receivable, total past due	23	24
Consumer Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans receivable, total past due	24	22
Consumer Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans receivable, total past due	807	808
Residential Portfolio Segment [Member]
Loans receivable, total past due		130
Loans receivable, current	22,652	9,552
Loans receivable	22,652	9,682
Loans receivable greater than 90 days and accruing		130
Residential Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Loans receivable, total past due
Residential Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans receivable, total past due
Residential Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans receivable, total past due		$ 130