Note 3 - Securities (Details) - Securities Available-for-sale (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized costs	$ 225,279	$ 203,268
Securities available-for-sale, gross unrealized gains	2,148	1,255
Securities available-for-sale, gross unrealized losses	4,583	22,811
Securities available-for-sale, fair value	222,844us-gaap_AvailableForSaleSecurities	181,712us-gaap_AvailableForSaleSecurities
US Government Agencies Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized costs	197,740	169,818
Securities available-for-sale, gross unrealized gains	973	199
Securities available-for-sale, gross unrealized losses	4,494	22,163
Securities available-for-sale, fair value	194,219	147,854
US States and Political Subdivisions Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized costs	18,529	22,830
Securities available-for-sale, gross unrealized gains	851	746
Securities available-for-sale, gross unrealized losses		120
Securities available-for-sale, fair value	19,380	23,456
Collateralized Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized costs	1,830	2,627
Securities available-for-sale, gross unrealized gains	184	213
Securities available-for-sale, fair value	2,014	2,840
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized costs	6,991	7,804
Securities available-for-sale, gross unrealized gains	140	97
Securities available-for-sale, gross unrealized losses	27	506
Securities available-for-sale, fair value	7,104	7,395
Other Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities available-for-sale, amortized costs	189	189
Securities available-for-sale, gross unrealized losses	62	22
Securities available-for-sale, fair value	$ 127	$ 167

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

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-Publisher FASB

-Name Accounting Standards Codification

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

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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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