Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	$ 186,262	$ 185,250
Investment securities available for sale, gross unrealized gains	3,245	2,400
Investment securities available for sale, gross unrealized losses	(2,483)	(2,271)
Investment securities available for sale, at fair value	187,024us-gaap_AvailableForSaleSecurities	185,379us-gaap_AvailableForSaleSecurities
Investment securities held to maturity, at amortized cost	66,742us-gaap_HeldToMaturitySecurities	67,866us-gaap_HeldToMaturitySecurities
Investment securities held to maturity, gross unrealized gains	1,136	531
Investment securities held to maturity, gross unrealized losses	0	(144)
Investment securities held to maturity, at fair value	67,878	68,253
Collateralized Mortgage Obligations [Member]
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	99,421	98,626
Investment securities available for sale, gross unrealized gains	1,508	692
Investment securities available for sale, gross unrealized losses	(142)	(96)
Investment securities available for sale, at fair value	100,787	99,222
Investment securities held to maturity, at amortized cost	66,721	67,845
Investment securities held to maturity, gross unrealized gains	1,136	531
Investment securities held to maturity, gross unrealized losses	0	(144)
Investment securities held to maturity, at fair value	67,857	68,232
Collateralized Mortgage Backed Securities [Member]
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	12,474	13,271
Investment securities available for sale, gross unrealized gains	549	564
Investment securities available for sale, gross unrealized losses	(45)	(33)
Investment securities available for sale, at fair value	12,978	13,802
US States and Political Subdivisions Debt Securities [Member]
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	17,031	15,784
Investment securities available for sale, gross unrealized gains	404	363
Investment securities available for sale, gross unrealized losses	(47)	(40)
Investment securities available for sale, at fair value	17,388	16,107
Corporate Debt Securities [Member]
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	33,817	33,840
Investment securities available for sale, gross unrealized gains	555	621
Investment securities available for sale, gross unrealized losses	(51)	(34)
Investment securities available for sale, at fair value	34,321	34,427
Asset-backed Securities [Member]
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	18,164	18,353
Investment securities available for sale, gross unrealized gains	222	152
Investment securities available for sale, gross unrealized losses	0	0
Investment securities available for sale, at fair value	18,386	18,505
Collateralized Debt Obligations [Member]
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	5,240	5,261
Investment securities available for sale, gross unrealized gains	0	0
Investment securities available for sale, gross unrealized losses	(2,198)	(2,068)
Investment securities available for sale, at fair value	3,042	3,193
Other Debt Obligations [Member]
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	115	115
Investment securities available for sale, gross unrealized gains	7	8
Investment securities available for sale, gross unrealized losses	0	0
Investment securities available for sale, at fair value	122	123
Investment securities held to maturity, at amortized cost	20	20
Investment securities held to maturity, gross unrealized gains	0	0
Investment securities held to maturity, gross unrealized losses	0	0
Investment securities held to maturity, at fair value	20	20
US Government Agencies Debt Securities [Member]
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities held to maturity, at amortized cost	1	1
Investment securities held to maturity, gross unrealized gains	0	0
Investment securities held to maturity, gross unrealized losses	0	0
Investment securities held to maturity, at fair value	$ 1	$ 1

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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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