Note 4 - Investment Securities Available-for-sale (Details) - Reconciliation of Available-for-sale Securities (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Note 4 - Investment Securities Available-for-sale (Details) - Reconciliation of Available-for-sale Securities [Line Items]
Investment securities available for sale, amortized cost	$ 211,537	$ 212,832
Investment securities available for sale, gross unrealized gains	1,593	753
Investment securities available for sale, gross unrealized losses	(1,162)	(2,074)
Investment securities available for sale, fair value	211,968us-gaap_AvailableForSaleSecurities	211,511us-gaap_AvailableForSaleSecurities
US Government Agencies Debt Securities [Member]
Note 4 - Investment Securities Available-for-sale (Details) - Reconciliation of Available-for-sale Securities [Line Items]
Investment securities available for sale, amortized cost	3,167	3,930
Investment securities available for sale, gross unrealized gains	68	35
Investment securities available for sale, fair value	3,235	3,965
US States and Political Subdivisions Debt Securities [Member]
Note 4 - Investment Securities Available-for-sale (Details) - Reconciliation of Available-for-sale Securities [Line Items]
Investment securities available for sale, amortized cost	7,802	6,665
Investment securities available for sale, gross unrealized gains	94	84
Investment securities available for sale, gross unrealized losses	(26)	(17)
Investment securities available for sale, fair value	7,870	6,732
Collateralized Mortgage Obligations (Federal Agencies) [Member]
Note 4 - Investment Securities Available-for-sale (Details) - Reconciliation of Available-for-sale Securities [Line Items]
Investment securities available for sale, amortized cost	88,901	89,311
Investment securities available for sale, gross unrealized gains	497	13
Investment securities available for sale, gross unrealized losses	(711)	(1,550)
Investment securities available for sale, fair value	88,687	87,774
Other Mortgage-Backed (Federal Agencies) [Member]
Note 4 - Investment Securities Available-for-sale (Details) - Reconciliation of Available-for-sale Securities [Line Items]
Investment securities available for sale, amortized cost	78,626	78,532
Investment securities available for sale, gross unrealized gains	702	411
Investment securities available for sale, gross unrealized losses	(360)	(440)
Investment securities available for sale, fair value	78,968	78,503
SBA Loan-Backed (Federal Agencies) [Member]
Note 4 - Investment Securities Available-for-sale (Details) - Reconciliation of Available-for-sale Securities [Line Items]
Investment securities available for sale, amortized cost	33,041	34,394
Investment securities available for sale, gross unrealized gains	232	210
Investment securities available for sale, gross unrealized losses	(65)	(67)
Investment securities available for sale, fair value	$ 33,208	$ 34,537

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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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