Note 2 - Securities (Details) - Debt Securities by Maturity	Mar. 31, 2016 USD ($)
Note 2 - Securities (Details) - Debt Securities by Maturity [Line Items]
Due in 2016	1.47%
Due in 2016	$ 36,231,000
Due in 2016	$ 36,259,000
Due in 2017 through 2021	1.76%
Due in 2017 through 2021	$ 122,550,000
Due in 2017 through 2021	$ 123,425,000
Due in 2022 through 2026	3.25%
Due in 2022 through 2026	$ 52,425,000
Due in 2022 through 2026	$ 53,629,000
Due in 2027 and beyond	3.48%
Due in 2027 and beyond	$ 64,786,000
Due in 2027 and beyond	$ 66,062,000
	2.29%
	$ 339,690,000
	$ 343,805,000
Collateralized Mortgage Backed Securities [Member]
Note 2 - Securities (Details) - Debt Securities by Maturity [Line Items]
No single maturity, weighted average yield	1.77%
No single maturity, amortized cost	$ 61,744,000
No single maturity, fair value	$ 62,461,000
Other Debt Obligations [Member]
Note 2 - Securities (Details) - Debt Securities by Maturity [Line Items]
No single maturity, weighted average yield	1.53%
No single maturity, amortized cost	$ 1,954,000
No single maturity, fair value	$ 1,969,000