Note 3 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Note 3 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	$ 288,792	$ 185,250
Investment securities available for sale, gross unrealized gains	1,399	2,400
Investment securities available for sale, gross unrealized losses	(5,396)	(2,271)
Investment securities available for sale, at fair value	284,795	185,379
Investment securities held to maturity, at amortized cost	172,277	67,866
Investment securities held to maturity, gross unrealized gains	441	531
Investment securities held to maturity, gross unrealized losses	(873)	(144)
Investment securities held to maturity, at fair value	171,845	68,253
Collateralized Mortgage Obligations [Member]
Note 3 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	180,795	98,626
Investment securities available for sale, gross unrealized gains	523	692
Investment securities available for sale, gross unrealized losses	(3,173)	(96)
Investment securities available for sale, at fair value	178,145	99,222
Investment securities held to maturity, at amortized cost	146,458	67,845
Investment securities held to maturity, gross unrealized gains	402	531
Investment securities held to maturity, gross unrealized losses	(780)	(144)
Investment securities held to maturity, at fair value	146,080	68,232
Collateralized Mortgage Backed Securities [Member]
Note 3 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	10,073	13,271
Investment securities available for sale, gross unrealized gains	176	564
Investment securities available for sale, gross unrealized losses	(78)	(33)
Investment securities available for sale, at fair value	10,171	13,802
Investment securities held to maturity, at amortized cost	7,732
Investment securities held to maturity, gross unrealized losses	(21)
Investment securities held to maturity, at fair value	7,711
US States and Political Subdivisions Debt Securities [Member]
Note 3 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	22,814	15,784
Investment securities available for sale, gross unrealized gains	562	363
Investment securities available for sale, gross unrealized losses	(32)	(40)
Investment securities available for sale, at fair value	23,344	16,107
Corporate Debt Securities [Member]
Note 3 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	54,294	33,840
Investment securities available for sale, gross unrealized gains	135	621
Investment securities available for sale, gross unrealized losses	(300)	(34)
Investment securities available for sale, at fair value	54,129	34,427
Asset-backed Securities [Member]
Note 3 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities available for sale, at amortized cost	17,631	18,353
Investment securities available for sale, gross unrealized gains	0	152
Investment securities available for sale, gross unrealized losses	(626)	0
Investment securities available for sale, at fair value	17,005	18,505
Collateralized Debt Obligations [Member]
Note 3 - 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	(1,187)	(2,068)
Investment securities available for sale, at fair value	1,883	3,193
Other Debt Obligations [Member]
Note 3 - 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	3	8
Investment securities available for sale, gross unrealized losses	0	0
Investment securities available for sale, at fair value	118	123
Investment securities held to maturity, at amortized cost	1,020	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	1,020	20
US Government Agencies Debt Securities [Member]
Note 3 - Investment Securities (Details) - Unrealized Gain (Loss) on Investments [Line Items]
Investment securities held to maturity, at amortized cost	17,067	1
Investment securities held to maturity, gross unrealized gains	39	0
Investment securities held to maturity, gross unrealized losses	(72)	0
Investment securities held to maturity, at fair value	$ 17,034	$ 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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