Summary of Significant Accounting Policies (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Numerator:
Net income	$ 2,131us-gaap_NetIncomeLoss	$ 2,439us-gaap_NetIncomeLoss
Less: Net income allocated to unvested participating securities	32	21
Net income available to common stockholders	$ 2,099	$ 2,418
Denominator:
Denominator for basic earnings per share— weighted average shares	5,710	5,690
Effect of dilutive securities:
Stock options	52	67
Denominator for diluted earnings per share — adjusted weighted-average shares and assumed conversions	5,762	5,757
Basic	$ 0.37us-gaap_EarningsPerShareBasic	$ 0.43us-gaap_EarningsPerShareBasic
Diluted	$ 0.36us-gaap_EarningsPerShareDiluted	$ 0.42us-gaap_EarningsPerShareDiluted

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