Net Income Per Common Share - Summary of Net Income Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Earnings Per Share [Line Items]
Net income	$ 13,595	$ 7,350	$ 17,733	$ 17,673
Basic weighted-average common shares outstanding	37,235	30,378	37,063	30,373
Effect of dilutive stock options	324	165	347	81
Effect of dilutive restricted stock awards	1,341		1,316
Diluted weighted-average common shares outstanding	38,900	30,543	38,726	30,454
Basic income per common share outstanding	$ 0.37	$ 0.24	$ 0.48	$ 0.58
Diluted income per common share outstanding	$ 0.35	$ 0.24	$ 0.46	$ 0.58
Stock Options [Member] \| Nonvested Restricted Stock [Member]
Earnings Per Share [Line Items]
Stock options and nonvested restricted stock	339	2,183	379	2,183

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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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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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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