Note 6 - Loans Receivable and Allowance for Loan Losses - Past Due Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
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	12	7,657
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans receivable, total past due	13,280	5,913
Commercial Real Estate Portfolio Segment [Member]
Loans receivable, total past due	13,292	13,570
Loans receivable, current	363,174	336,156
Loans receivable	376,466	349,726
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	56	117
Construction and Land Development Portfolio Segment [Member]
Loans receivable, total past due	56	117
Loans receivable, current	48,927	46,430
Loans receivable	48,983	46,547
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		1,661
Commercial Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans receivable, total past due	747	997
Commercial Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans receivable, total past due	3,149	3,156
Commercial Portfolio Segment [Member]
Loans receivable, total past due	3,896	5,814
Loans receivable, current	182,230	176,036
Loans receivable	186,126	181,850
Loans receivable greater than 90 days and accruing
Owner Occupied Real Estate [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Loans receivable, total past due		800
Owner Occupied Real Estate [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans receivable, total past due		469
Owner Occupied Real Estate [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans receivable, total past due	1,874	2,894
Owner Occupied Real Estate [Member]
Loans receivable, total past due	1,874	4,163
Loans receivable, current	266,561	242,235
Loans receivable	268,435	246,398
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		285
Consumer Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Loans receivable, total past due	22	192
Consumer Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans receivable, total past due	995	542
Consumer Portfolio Segment [Member]
Loans receivable, total past due	1,017	1,019
Loans receivable, current	57,563	47,107
Loans receivable	58,580	48,126
Loans receivable greater than 90 days and accruing	16
Residential Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Loans receivable, total past due		132
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	137
Residential Portfolio Segment [Member]
Loans receivable, total past due	137	132
Loans receivable, current	6,772	2,248
Loans receivable	6,909	2,380
Loans receivable greater than 90 days and accruing	137
Financing Receivables, 30 to 59 Days Past Due [Member]
Loans receivable, total past due		2,878
Financing Receivables, 60 to 89 Days Past Due [Member]
Loans receivable, total past due	781	9,315
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans receivable, total past due	19,491	12,622
Loans receivable, total past due	20,272	24,815
Loans receivable, current	925,227	850,212
Loans receivable	945,499	875,027
Loans receivable greater than 90 days and accruing	$ 153