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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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