Note 2 - Investment Securities (Details) - Investment Securities - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Schedule of Investments [Line Items]
Investment securities available for sale, amortized cost	$ 243,948,000	$ 286,779,000
Investment securities available for sale, gross unrealized gains	4,987,000	6,614,000
Investment securities available for sale, gross unrealized losses	640,000	1,094,000
Investment securities available for sale, at fair value	248,294,725	292,298,910
Securities held to maturity, amortized cost	508,456	507,309
Securities held to maturity, gross unrealized gains	2,000	5,000
Securities held to maturity, at fair value	510,000	512,000
Investment securities available for sale, gross unrealized losses	0	0
US Government Agencies Debt Securities [Member]
Schedule of Investments [Line Items]
Investment securities available for sale, amortized cost	30,850,000
Investment securities available for sale, gross unrealized gains	541,000
Investment securities available for sale, gross unrealized losses	6,000
Investment securities available for sale, at fair value	31,385,000
Securities held to maturity, amortized cost		507,000
Securities held to maturity, gross unrealized gains		5,000
Securities held to maturity, at fair value		512,000
Investment securities available for sale, gross unrealized losses		0
Collateralized Mortgage Backed Securities [Member]
Schedule of Investments [Line Items]
Investment securities available for sale, amortized cost	128,820,000	170,443,000
Investment securities available for sale, gross unrealized gains	3,141,000	4,384,000
Investment securities available for sale, gross unrealized losses	277,000	547,000
Investment securities available for sale, at fair value	131,684,000	174,280,000
US States and Political Subdivisions Debt Securities [Member]
Schedule of Investments [Line Items]
Investment securities available for sale, amortized cost	55,534,000	54,014,000
Investment securities available for sale, gross unrealized gains	1,305,000	1,797,000
Investment securities available for sale, gross unrealized losses	8,000	109,000
Investment securities available for sale, at fair value	56,831,000	55,702,000
Corporate Debt Securities [Member]
Schedule of Investments [Line Items]
Investment securities available for sale, amortized cost	28,744,000	31,411,000
Investment securities available for sale, gross unrealized gains	0	36,000
Investment securities available for sale, gross unrealized losses	349,000	362,000
Investment securities available for sale, at fair value	28,395,000	31,085,000
US Government Agencies Debt Securities [Member]
Schedule of Investments [Line Items]
Investment securities available for sale, amortized cost		30,911,000
Investment securities available for sale, gross unrealized gains		397,000
Investment securities available for sale, gross unrealized losses		76,000
Investment securities available for sale, at fair value		$ 31,232,000
Securities held to maturity, amortized cost	508,000
Securities held to maturity, gross unrealized gains	2,000
Securities held to maturity, at fair value	510,000
Investment securities available for sale, gross unrealized losses	$ 0

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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-Name Accounting Standards Codification
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