Net Income Per Common Share - Summary of Net Income Per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Earnings Per Share [Line Items]
Net income	$ 4,138	$ 10,323
Basic weighted-average common shares outstanding	36,888,718	30,368,240
Effect of dilutive restricted stock awards	1,409,647	4,451
Effect of dilutive stock options	302,991	0
Diluted weighted-average common shares outstanding	38,601,356	30,372,691
Basic income per common share outstanding	$ 0.11	$ 0.34
Diluted income per common share outstanding	$ 0.11	$ 0.34
Stock Options [Member] \| Nonvested Restricted Stock [Member]
Earnings Per Share [Line Items]
Stock options and nonvested restricted stock	386,996	2,221,940

Earnings Per Share [Line Items]

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Incremental common shares attributable to restricted stock awards.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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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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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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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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