Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Note 5 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	$ 209,778	$ 185,250
Investment securities available for sale, gross unrealized gains	2,212	2,400
Investment securities available for sale, gross unrealized losses	(2,871)	(2,271)
Investment securities available for sale, at fair value	209,119	185,379
Investment securities held to maturity at amortized cost	140,116	67,866
Investment securities held to maturity, gross unrealized gains	1,648	531
Investment securities held to maturity, gross unrealized losses	(245)	(144)
Investment securities held to maturity, at fair value	141,519	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	127,369	98,626
Investment securities available for sale, gross unrealized gains	1,371	692
Investment securities available for sale, gross unrealized losses	(353)	(96)
Investment securities available for sale, at fair value	128,387	99,222
Investment securities held to maturity at amortized cost	120,051	67,845
Investment securities held to maturity, gross unrealized gains	1,574	531
Investment securities held to maturity, gross unrealized losses	(206)	(144)
Investment securities held to maturity, at fair value	121,419	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	10,287	13,271
Investment securities available for sale, gross unrealized gains	188	564
Investment securities available for sale, gross unrealized losses	(51)	(33)
Investment securities available for sale, at fair value	10,424	13,802
Investment securities held to maturity at amortized cost	7,954
Investment securities held to maturity, gross unrealized gains	73
Investment securities held to maturity, gross unrealized losses	0
Investment securities held to maturity, at fair value	8,027
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	21,820	15,784
Investment securities available for sale, gross unrealized gains	374	363
Investment securities available for sale, gross unrealized losses	(110)	(40)
Investment securities available for sale, at fair value	22,084	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	29,313	33,840
Investment securities available for sale, gross unrealized gains	275	621
Investment securities available for sale, gross unrealized losses	(367)	(34)
Investment securities available for sale, at fair value	29,221	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	17,804	18,353
Investment securities available for sale, gross unrealized gains	0	152
Investment securities available for sale, gross unrealized losses	(590)	0
Investment securities available for sale, at fair value	17,214	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	3,070	5,261
Investment securities available for sale, gross unrealized gains	0	0
Investment securities available for sale, gross unrealized losses	(1,400)	(2,068)
Investment securities available for sale, at fair value	1,670	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	4	8
Investment securities available for sale, gross unrealized losses	0	0
Investment securities available for sale, at fair value	119	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	12,091	1
Investment securities held to maturity, gross unrealized gains	1	0
Investment securities held to maturity, gross unrealized losses	(39)	0
Investment securities held to maturity, at fair value	$ 12,053	$ 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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