Earnings Per Share - Computation of Basic and Diluted Earnings Per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Earnings Per Share Basic And Diluted [Line Items]
Net income available to common shareholders	$ 2,037	$ 1,856	$ 6,032	$ 5,619	$ 7,073
Weighted average number of common shares outstanding used in computation of basic earnings per common share	7,059,953	7,217,006	7,137,398	7,218,603
Effect of dilutive securities:
Weighted average number of common shares outstanding plus effect of dilutive securities used in computation of diluted earnings per common share	7,102,443	7,252,581	7,172,669	7,247,084
Basic earnings per share	$ 0.29	$ 0.26	$ 0.85	$ 0.78
Diluted earnings per share	$ 0.29	$ 0.26	$ 0.84	$ 0.78
Restricted Stock [Member]
Effect of dilutive securities:
Effect of dilutive securities	15,546	9,326	8,991	4,812
Stock Options [Member]
Effect of dilutive securities:
Effect of dilutive securities	15,369	13,980	14,920	12,385
Stock Warrants [Member]
Effect of dilutive securities:
Effect of dilutive securities	11,575	12,269	11,360	11,284

Earnings per share basic and diluted.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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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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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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