Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common stock and additional paid-in capital	Retained earnings	Accumulated other comprehensive income (loss)
Balance, beginning balance at Dec. 31, 2013	$ 146,098us-gaap_StockholdersEquity	$ 58,501	$ 94,000	$ (6,403)
Balance, beginning period (in shares) at Dec. 31, 2013		10,671,192
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	3,428us-gaap_NetIncomeLoss		3,428
Net unrealized gain on securities available for sale, net of tax	4,824			4,824
Net unrealized loss on securities transferred from available for sale to held to maturity, net of tax	0
Comprehensive income	8,252us-gaap_ComprehensiveIncomeNetOfTax		3,428	4,824
Cash dividends declared on common stock ($0.20 and $0.21 for the three months ended March 31, 2014 and 2015, respectively)	(2,139)us-gaap_DividendsCommonStockCash		(2,139)
Equity compensation expense	102	102
Issuance of restricted stock (in shares)		25,843
Issuance of restricted stock		1	(1)
Proceeds from sale of common stock (in shares)		6,237
Proceeds from sale of common stock	103	103
Balance, ending period at Mar. 31, 2014	152,416us-gaap_StockholdersEquity	58,707	95,288	(1,579)
Balance, ending balance (in shares) at Mar. 31, 2014	10,703,272us-gaap_CommonStockSharesOutstanding	10,703,272
Balance, beginning balance at Dec. 31, 2014	161,554us-gaap_StockholdersEquity	59,389	99,816	2,349
Balance, beginning period (in shares) at Dec. 31, 2014	10,724,359us-gaap_CommonStockSharesOutstanding	10,724,359
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	4,175us-gaap_NetIncomeLoss		4,175
Net unrealized gain on securities available for sale, net of tax	57			57
Net unrealized loss on securities transferred from available for sale to held to maturity, net of tax	(19)			(19)
Comprehensive income	4,213us-gaap_ComprehensiveIncomeNetOfTax		4,175	38
Cash dividends declared on common stock ($0.20 and $0.21 for the three months ended March 31, 2014 and 2015, respectively)	(2,255)us-gaap_DividendsCommonStockCash		(2,255)
Equity compensation expense	74	74
Issuance of restricted stock (in shares)		13,650
Payment for repurchase of common stock	(180)	(180)
Payment for repurchase of common stock, shares		(10,138)
Proceeds from sale of common stock (in shares)		6,548
Proceeds from sale of common stock	110	110
Balance, ending period at Mar. 31, 2015	$ 163,516us-gaap_StockholdersEquity	$ 59,393	$ 101,736	$ 2,387
Balance, ending balance (in shares) at Mar. 31, 2015	10,734,419us-gaap_CommonStockSharesOutstanding	10,734,419

Available-for-sale Securities, Transferred to Held-to-maturity Securities, Unrealized Gain (Loss)

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This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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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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Number of new stock issued during the period.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Aggregate value of stock related to Restricted Stock Awards issued during the period.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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