Earnings and Dividends per Share - Number of Shares Outstanding for Calculation of Earnings Per Share (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Numerator (for basic and diluted earnings per share)
Net income	$ 1,864	$ 5,763
Denominator
Basic weighted-average shares outstanding	34,835,550	34,592,803
Common stock equivalents arising from stock options and restricted stock awards	524,000	48,000
Diluted weighted-average shares outstanding	35,360,042	34,641,390

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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