Net Income Per Share - Additional Information (Detail) - $ / shares	Jun. 30, 2019	Dec. 31, 2018	May 01, 2013	Apr. 30, 2013
Schedule Of Earnings Per Share [Line Items]
Common stock, shares outstanding	45,549,185	45,336,278
Number of new common stock issued	45,571,743	45,365,170
Par value of common stock issued	$ 0.01	$ 0.01		$ 0.01
Exercise price of common stock			$ 16.67
Warrants outstanding	4,877,783

Schedule Of Earnings Per Share [Line Items]

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Exercise price per share or per unit of warrants or rights outstanding.

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Number of warrants or rights outstanding.

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Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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