Stock-Based Awards - Stock-Based Awards - Summary of Stock Options, Restricted Stock and Restricted Stock Unit Activity (Detail)	3 Months Ended
Mar. 31, 2020 shares
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, beginning balance	485,536
Options, Exercised/vested	(107,000)
Options, Forfeitures	(63,536)
Options, ending balance	315,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested Beginning Balance, Shares	3,244,558
Granted, Shares	1,436,089
Vested, Shares	(936,186)
Forfeited, Shares	(23,483)
Unvested Ending Balance, Shares	3,720,978
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested Beginning Balance, Shares	39,278
Granted, Shares	32,901
Vested, Shares	(27,130)
Forfeited, Shares	(1,993)
Unvested Ending Balance, Shares	43,056
Performance Based Restricted Stock Unites (PRSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested Beginning Balance, Shares	232,610
Granted, Shares	117,013
Unvested Ending Balance, Shares	349,623

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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

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

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