Note 13 - Condensed Financial Statements of Parent Company (Details) - Condensed Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Assets
Cash due from subsidiaries	$ 12,894us-gaap_CashAndDueFromBanks	$ 13,283us-gaap_CashAndDueFromBanks	$ 14,783us-gaap_CashAndDueFromBanks	$ 11,897us-gaap_CashAndDueFromBanks
Interest-bearing deposits	102,548us-gaap_InterestBearingDepositsInBanks	98,066us-gaap_InterestBearingDepositsInBanks
Securities available for sale	222,844us-gaap_AvailableForSaleSecurities	181,712us-gaap_AvailableForSaleSecurities
Securities held to maturity (fair value approximates $450 at December 31, 2014 and $0 at December 31, 2013)	161,452us-gaap_HeldToMaturitySecurities	163,983us-gaap_HeldToMaturitySecurities
Other assets	7,767us-gaap_OtherAssets	13,341us-gaap_OtherAssets
Total assets	1,154,731us-gaap_Assets	1,110,630us-gaap_Assets
Liabilities and Stockholders’ Equity
Other liabilities	5,932us-gaap_OtherLiabilities	4,610us-gaap_OtherLiabilities
Stockholders’ equity	166,303us-gaap_StockholdersEquity	145,892us-gaap_StockholdersEquity	150,109us-gaap_StockholdersEquity	141,299us-gaap_StockholdersEquity
Total liabilities and stockholders’ equity	1,154,731	1,110,630
Parent Company [Member]
Assets
Cash due from subsidiaries	10	27
Interest-bearing deposits	477	690
Securities available for sale	127	623
Securities held to maturity (fair value approximates $450 at December 31, 2014 and $0 at December 31, 2013)	452
Investments in subsidiaries, at equity	165,647	144,513
Other assets	188	478
Total assets	166,901	146,331
Liabilities and Stockholders’ Equity
Other liabilities	598	439
Stockholders’ equity	166,303	145,892
Total liabilities and stockholders’ equity	$ 166,901	$ 146,331

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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

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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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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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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Amount of liabilities and equity items, including the portion of equity attributable to noncontrolling interests, if any.

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The aggregate carrying amounts, as of the balance sheet date, of assets not separately disclosed in the balance sheet.

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The aggregate carrying amount, as of the balance sheet date, of liabilities not separately disclosed in the balance sheet.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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