Equity-Based Compensation - Schedule of Activity Related to Stock Option Awards (Detail) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Options, Outstanding, Beginning Balance	764,577
Options, Granted	449,326
Options, Forfeited	(109,251)
Options, Expired	(8,593)
Options, Exercised	(198,437)
Options, Outstanding, Ending Balance	897,622
Options, Exercisable at September 30, 2019	411,309
Weighted Average Exercise Price, Outstanding, Beginning Balance	$ 18.05
Weighted Average Exercise Price, Granted	25.95
Weighted Average Exercise Price, Forfeited	21.38
Weighted Average Exercise Price, Expired	18.52
Weighted Average Exercise Price, Exercised	18.03
Weighted Average Exercise Price, Outstanding, Ending Balance	21.60
Weighted Average Exercise Price, Exercisable at September 30, 2019	$ 18.27
Weighted Average Remaining Contractual Life, Outstanding at September 30, 2019	7 years 6 months 18 days
Weighted Average Remaining Contractual Life, Exercisable at September 30, 2019	5 years 11 months 19 days
Aggregate Intrinsic Value, Outstanding at September 30, 2019	$ 4,336
Aggregate Intrinsic Value, Exercisable at September 30, 2019	$ 3,309

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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Net number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of non-vested options forfeited.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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