Note 4 - Allowance for Loan Losses (Details) - Loans by Credit Quality Indicators - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Construction loans:
Loans	$ 381,063	$ 367,358
Pass [Member]
Construction loans:
Loans	378,320	358,751
Special Mention [Member]
Construction loans:
Loans	687	6,531
Substandard [Member]
Construction loans:
Loans	1,641	1,650
Substandard Nonaccrual [Member]
Construction loans:
Loans	415	426
Construction Loan Portfolio Segment [Member] | Residential [Member]
Construction loans:
Loans	10,983	11,779
Construction Loan Portfolio Segment [Member] | Residential [Member] | Pass [Member]
Construction loans:
Loans	10,983	11,779
Construction Loan Portfolio Segment [Member] | Land Acquisition, Development and Commercial [Member]
Construction loans:
Loans	30,167	27,440
Construction Loan Portfolio Segment [Member] | Land Acquisition, Development and Commercial [Member] | Pass [Member]
Construction loans:
Loans	30,157	27,429
Construction Loan Portfolio Segment [Member] | Land Acquisition, Development and Commercial [Member] | Substandard Nonaccrual [Member]
Construction loans:
Loans	10	11
Real Estate Portfolio Segment [Member] | Residential [Member]
Construction loans:
Loans	105,055	100,268
Real Estate Portfolio Segment [Member] | Residential [Member] | Pass [Member]
Construction loans:
Loans	104,859	95,809
Real Estate Portfolio Segment [Member] | Residential [Member] | Special Mention [Member]
Construction loans:
Loans		4,212
Real Estate Portfolio Segment [Member] | Residential [Member] | Substandard [Member]
Construction loans:
Loans	196	247
Real Estate Portfolio Segment [Member] | Commercial [Member}
Construction loans:
Loans	147,561	140,952
Real Estate Portfolio Segment [Member] | Commercial [Member} | Pass [Member]
Construction loans:
Loans	145,762	138,034
Real Estate Portfolio Segment [Member] | Commercial [Member} | Special Mention [Member]
Construction loans:
Loans		1,155
Real Estate Portfolio Segment [Member] | Commercial [Member} | Substandard [Member]
Construction loans:
Loans	1,439	1,395
Real Estate Portfolio Segment [Member] | Commercial [Member} | Substandard Nonaccrual [Member]
Construction loans:
Loans	360	368
Commercial, Industrial and Agricultural Portfolio Segment [Member]
Construction loans:
Loans	52,913	53,012
Commercial, Industrial and Agricultural Portfolio Segment [Member] | Pass [Member]
Construction loans:
Loans	52,181	51,801
Commercial, Industrial and Agricultural Portfolio Segment [Member] | Special Mention [Member]
Construction loans:
Loans	687	1,164
Commercial, Industrial and Agricultural Portfolio Segment [Member] | Substandard Nonaccrual [Member]
Construction loans:
Loans	45	47
Equity Lines Portfolio Segment [Member]
Construction loans:
Loans	26,954	26,376
Equity Lines Portfolio Segment [Member] | Pass [Member]
Construction loans:
Loans	26,954	26,376
Consumer Portfolio Segment [Member]
Construction loans:
Loans	7,430	7,531
Consumer Portfolio Segment [Member] | Pass [Member]
Construction loans:
Loans	7,424	7,523
Consumer Portfolio Segment [Member] | Substandard [Member]
Construction loans:
Loans	$ 6	$ 8