Consolidated Balance Sheets (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Assets
Available-for-sale investment securities at amortized cost	$ 748,622	$ 632,967
Held-to-maturity investment securities at fair value	$ 48,774	$ 48,442
Stockholders’ Equity
Preferred stock - shares authorized	50,000us-gaap_PreferredStockSharesAuthorized	50,000us-gaap_PreferredStockSharesAuthorized
Preferred stock - shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Common stock - shares authorized	24,000,000us-gaap_CommonStockSharesAuthorized	24,000,000us-gaap_CommonStockSharesAuthorized
Common stock - shares issued	18,918,525us-gaap_CommonStockSharesIssued	15,426,973us-gaap_CommonStockSharesIssued
Treasury stock - shares	599,738us-gaap_TreasuryStockShares	590,246us-gaap_TreasuryStockShares

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Fair value of investments in debt securities classified as held-to-maturity.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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