Note 4 - Securities (Details) - Securities Reconcilliation (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Aug. 31, 2012
Available-for-sale securities
Available-for-sale securities, amortized costs	$ 184,397	$ 220,357
Available-for-sale securities, gross unrealized gains	3,231	1,684
Available-for-sale securities, gross unrealized losses	(642)	(5,401)
Available-for-sale securities, estimated fair value	186,986us-gaap_AvailableForSaleSecurities	216,640us-gaap_AvailableForSaleSecurities	18,800us-gaap_AvailableForSaleSecurities
Held-to-maturity securities
Held-to-maturity securities, amortized costs	36,806	36,696
Held-to-maturity securities, estimated fair value	37,118
US Government Agencies Debt Securities [Member]
Available-for-sale securities
Available-for-sale securities, amortized costs	6,351	6,580
Available-for-sale securities, gross unrealized gains	58
Available-for-sale securities, gross unrealized losses	(16)	(316)
Available-for-sale securities, estimated fair value	6,393	6,264
Obligations of State and Political Subdivisions [Member]
Available-for-sale securities
Available-for-sale securities, amortized costs	52,629	60,370
Available-for-sale securities, gross unrealized gains	1,788	672
Available-for-sale securities, gross unrealized losses	(54)	(1,833)
Available-for-sale securities, estimated fair value	54,363	59,209
Held-to-maturity securities
Held-to-maturity securities, amortized costs	36,806	36,696
Held-to-maturity securities, gross unrealized gains	712	36
Held-to-maturity securities, gross unrealized losses	(400)	(2,707)
Held-to-maturity securities, estimated fair value	37,118	34,025
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities
Available-for-sale securities, amortized costs	46,727	64,026
Available-for-sale securities, gross unrealized gains	457	318
Available-for-sale securities, gross unrealized losses	(169)	(1,353)
Available-for-sale securities, estimated fair value	47,015	62,991
Corporate Debt Securities [Member]
Available-for-sale securities
Available-for-sale securities, amortized costs	37,392	48,836
Available-for-sale securities, gross unrealized gains	475	282
Available-for-sale securities, gross unrealized losses	(133)	(888)
Available-for-sale securities, estimated fair value	37,734	48,230
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities
Available-for-sale securities, amortized costs	10,402	10,828
Available-for-sale securities, gross unrealized gains	60	24
Available-for-sale securities, gross unrealized losses	(73)	(380)
Available-for-sale securities, estimated fair value	10,389	10,472
Asset-backed Securities [Member]
Available-for-sale securities
Available-for-sale securities, amortized costs	30,896	29,717
Available-for-sale securities, gross unrealized gains	393	388
Available-for-sale securities, gross unrealized losses	(197)	(631)
Available-for-sale securities, estimated fair value	$ 31,092	$ 29,474

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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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