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Equity - Incentive Equity Awards - Additional Information (Detail) - USD ($) $ in Thousands |  |  |  |  |  |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | ---
May 20, 2019 | Feb. 01, 2019 | Nov. 01, 2018 | May 14, 2018 | Mar. 12, 2018 | Feb. 01, 2018 | Oct. 31, 2019 | Sep. 30, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stock options, outstanding |  |  |  |  |  |  |  |  | 15,619,123 | 19,263,000 |
Shares issued, exercise of stock options |  |  |  |  |  |  |  |  | 5,997,919 | 8,138,305 |
Proceeds from exercise of stock options, net of transaction costs |  |  |  |  |  |  |  |  | $ 24,478 | $ 26,402 | $ 638
Restricted Stock Units (RSUs) |  |  |  |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |  |  |  |
Restricted stock units, outstanding |  |  |  |  |  |  |  |  | 6,921,071 |  |
Percentage of outstanding shares on a fully diluted basis |  |  |  |  |  |  |  |  | 2.00% |  |
Stock units, Granted |  |  |  |  |  |  |  |  | 1,473,000 | 2,633,000 |
Restricted Stock Units (RSUs) | Stock Incentive Plan 2011 |  |  |  |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stock units, Granted | 45,163 | 757,800 |  | 190,034 |  | 1,305,575 |  |  |  |  |
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 | Vesting Period |  |  |  |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stock units, Granted |  |  | 90,000 |  | 970,000 |  |  |  |  |  |
Stock units, Vesting Period |  |  |  |  | 3 years |  |  |  |  |  |
Restricted Stock Units (RSUs) | Stock Incentive Plan 2011 | Vest over a three year period |  |  |  |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |  |  |  |
Shares issued, related to the vesting of RSUs |  |  |  |  |  |  |  |  | 387,715 |  |
Treasury shares for settlement of employee tax obligations |  |  |  |  |  |  |  |  | 139,928 |  |
Restricted Stock Units (RSUs) | Stock Incentive Plan 2011 | Employees |  |  |  |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stock units, Granted |  | 580,000 |  |  |  |  |  |  |  |  |
Stock Options |  |  |  |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |  |  |  |
Percentage of outstanding shares on a fully diluted basis |  |  |  |  |  |  |  |  | 4.00% |  |
Stock units, Vesting Period |  |  |  |  |  |  |  |  | 4 years |  |
Stock Options | Stock Incentive Plan 2011 |  |  |  |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stock options, Granted | 58,721 | 1,193,400 |  | 286,536 |  | 2,205,075 |  |  |  |  |
Stock units, Vesting Period |  | 4 years |  |  |  | 4 years |  |  | 4 years |  |
Performance-Based RSUs |  |  |  |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |  |  |  |
Shares issued, related to the vesting of RSUs |  |  |  |  |  |  | 2,436,750 | 2,499,750 |  |  |
Treasury shares for settlement of employee tax obligations |  |  |  |  |  |  | 1,069,377 | 764,819 |  |  |

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