Earning Per Share (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Basic Earnings Per Share
Net income	$ 1,976	$ 1,426
Dividends and accretion on preferred stock	(362)	(362)
Income available to common stockholders	1,614	1,064
Effect of Dilutive securities
Stock options and RRP grants
Diluted Earnings Per Share
Income available to common stockholders and assumed conversions	$ 1,614	$ 1,064
Weighted-Average Shares number of common shares, basic	7,037,166	6,928,238
Weighted-Average Shares, effect of dilutive securities stock option and RRP grants	157,926	61,227
Weighted-Average Shares income available to common stockholders and assumed conversions, diluted	7,195,092	6,989,465
Earnings per share, basic	$ 0.23	$ 0.15
Earnings per share, diluted	$ 0.22	$ 0.15

The amount resulting from the "as if" assumption that stock options or restrictive stock units were exercised for purposes of computing the dilutive effect of convertible securities.

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