Note 4 - Investment Securities (Details) - Investment Securities (USD $)	Mar. 31, 2015	Dec. 31, 2014
Schedule of Investments [Line Items]
Securities available for sale, amortized cost	$ 265,160,000	$ 286,779,000
Securities available for sale, gross unrealized gains	7,506,000	6,614,000
Securities available for sale, gross unrealized losses	183,000	1,094,000
Securities available for sale, fair value	272,483,000us-gaap_AvailableForSaleSecurities	292,299,000us-gaap_AvailableForSaleSecurities
Securities held to maturity, amortized cost	507,595us-gaap_HeldToMaturitySecurities	507,309us-gaap_HeldToMaturitySecurities
US Government Agencies Debt Securities [Member]
Schedule of Investments [Line Items]
Securities available for sale, amortized cost	30,896,000	30,911,000
Securities available for sale, gross unrealized gains	763,000	397,000
Securities available for sale, gross unrealized losses		76,000
Securities available for sale, fair value	31,659,000	31,232,000
Securities held to maturity, amortized cost	508,000	507,000
Securities held to maturity, gross unrealized gains	6,000	5,000
Securities held to maturity, fair value	514,000	512,000
Mortgage Backed [Member]
Schedule of Investments [Line Items]
Securities available for sale, amortized cost	151,504,000	170,443,000
Securities available for sale, gross unrealized gains	4,626,000	4,384,000
Securities available for sale, gross unrealized losses	41,000	547,000
Securities available for sale, fair value	156,089,000	174,280,000
Municipal Securities [Member]
Schedule of Investments [Line Items]
Securities available for sale, amortized cost	53,879,000	54,014,000
Securities available for sale, gross unrealized gains	2,063,000	1,797,000
Securities available for sale, gross unrealized losses	21,000	109,000
Securities available for sale, fair value	55,921,000	55,702,000
Corporate Debt Securities [Member]
Schedule of Investments [Line Items]
Securities available for sale, amortized cost	28,881,000	31,411,000
Securities available for sale, gross unrealized gains	54,000	36,000
Securities available for sale, gross unrealized losses	121,000	362,000
Securities available for sale, fair value	$ 28,814,000	$ 31,085,000

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

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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