Earnings Per Share - Weighted Average Number of Shares Used in Computing Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Net income	$ 1,026	$ 742	$ 3,096	$ 1,122
Weighted average shares outstanding, basic	13,080,372	10,488,227	13,059,845	8,175,431
Dilutive shares:
Weighted average shares outstanding, dilutive	13,142,549	10,557,623	13,128,715	8,242,700
Basic and diluted earnings per share	$ 0.08	$ 0.07	$ 0.24	$ 0.14
Stock Option
Dilutive shares:
Effect of dilutive securities	56,060	69,396	60,334	67,269
Restricted Shares
Dilutive shares:
Effect of dilutive securities	6,117		8,536

The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or 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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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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