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Equity - Incentive Equity Awards - Additional Information (Detail) - USD ($) $ in Thousands							1 Months Ended	9 Months Ended
	Jul. 13, 2020	Jul. 01, 2020	Mar. 02, 2020	Feb. 03, 2020	May 20, 2019	Feb. 01, 2019	Jun. 01, 2020	Sep. 30, 2020	Sep. 30, 2019
Stockholders Equity Note [Line Items]
Shares issued, exercise of stock options								642,756	5,122,107
Proceeds from exercise of stock options, net of transaction costs								$ 1,861	$ 19,544
Stock Incentive Plan 2011
Stockholders Equity Note [Line Items]
Stock options, outstanding								17,478,906
Restricted Stock Units (RSUs)
Stockholders Equity Note [Line Items]
Shares issued, related to the vesting of RSUs								1,206,494	1,533,061
Treasury shares for settlement of employee tax obligations								440,573	580,765
Restricted Stock Units (RSUs) | Stock Incentive Plan 2011
Stockholders Equity Note [Line Items]
Restricted stock units, outstanding								7,727,158
Percentage of outstanding shares on a fully diluted basis								2.00%
Stock units, Granted			821,950		45,163	757,800
Stock units, Vesting Period			3 years		3 years	3 years	3 years
Stock units, additional granted					20,000
Restricted Stock Units (RSUs) | Stock Incentive Plan 2011 | Employees
Stockholders Equity Note [Line Items]
Stock units, Granted		100,000		1,253,400		580,000	782,520
Restricted Stock Units (RSUs) | Stock Incentive Plan 2020
Stockholders Equity Note [Line Items]
Stock units, Granted	164,657
Stock units, Vesting Period	3 years
Stock Options | Stock Incentive Plan 2011
Stockholders Equity Note [Line Items]
Percentage of outstanding shares on a fully diluted basis								4.00%
Stock units, Vesting Period				4 years		4 years
Stock options, Granted				1,875,000	58,721	1,193,400
Stock Options | Stock Incentive Plan 2020
Stockholders Equity Note [Line Items]
Stock options, Granted	210,764
Performance-Based RSUs
Stockholders Equity Note [Line Items]
Shares issued, related to the vesting of RSUs								1,107,660
Treasury shares for settlement of employee tax obligations								461,820

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