Note 4 - Maturities of Debt Securities (Details) - USD ($)	Jun. 30, 2016	Dec. 31, 2015
Collateralized Mortgage Backed Securities [Member]
Residential mortgage-backed securities	$ 95,634,000
Residential mortgage-backed securities	$ 97,240,000
Residential mortgage-backed securities	2.24%
Residential mortgage-backed securities	$ 0
Residential mortgage-backed securities	$ 0
Residential mortgage-backed securities	0.00%
Available-for-sale Securities	$ 97,240,000	$ 85,152,000
Within one year	22,691,000
Within one year	$ 22,715,000
Within one year	0.77%
Within one year	$ 0
Within one year	$ 0
Within one year	0.00%
Due from one year to five years	$ 22,437,000
Due from one year to five years	$ 22,633,000
Due from one year to five years	1.93%
Due from one year to five years	$ 0
Due from one year to five years	$ 0
Due from one year to five years	0.00%
Due from five years to ten years	$ 16,604,000
Due from five years to ten years	$ 17,096,000
Due from five years to ten years	2.95%
Due from five years to ten years	$ 0
Due from five years to ten years	$ 0
Due from five years to ten years	0.00%
Due after ten years	$ 31,213,000
Due after ten years	$ 31,827,000
Due after ten years	2.96%
Due after ten years	$ 1,038,000
Due after ten years	$ 1,038,000
Due after ten years	3.00%
	$ 92,945,000
	$ 94,271,000
	2.18%
	$ 1,038,000
	$ 1,038,000
	3.00%
Total	$ 188,579,000
Available-for-sale Securities	$ 191,511,000	$ 198,585,000
Total	2.21%
Total	$ 1,038,000
Total	$ 1,038,000
Total	3.00%