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Equity - Incentive Equity Awards - Additional Information (Detail) - USD ($) $ in Thousands |  |  |  |  |  | 9 Months Ended
--- | --- | --- | --- | --- | --- | ---
Jun. 14, 2021 | Jan. 04, 2021 | Jun. 01, 2020 | Mar. 02, 2020 | Feb. 03, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |
Stock Options Issued |  |  |  |  |  |  | 994,921 | 642,756
Proceeds from exercise of stock options, net of transaction costs |  |  |  |  |  |  | $ 2,615 | $ 1,861
Stock Incentive Plan 2020 |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |
Stock options, outstanding |  |  |  |  |  |  | 19,145,833 |
Restricted Stock Units (RSUs) |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |
Shares issued, related to the vesting of RSUs |  |  |  |  |  |  | 1,202,590 | 1,206,494
Treasury shares for settlement of employee tax obligations |  |  |  |  |  |  | 454,973 | 440,573
Restricted Stock Units (RSUs) | Stock Incentive Plan 2020 |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |
Restricted stock units, outstanding |  |  |  |  |  |  | 10,307,168 |
Percentage of outstanding shares on a fully diluted basis |  |  |  |  |  |  | 2.00% |
Stock units, Granted |  | 218,000 | 3,265,700 |  |  |  |  |
Stock units, Vesting Period |  | 3 years | 3 years |  |  |  |  |
Restricted Stock Units (RSUs) | Stock Incentive Plan 2011 |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |
Stock units, Granted |  |  |  | 782,520 | 821,950 |  |  |
Restricted Stock Units (RSUs) | Employees | Stock Incentive Plan 2020 |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |
Stock units, Granted |  |  | 1,345,800 |  |  |  |  |
Restricted Stock Units (RSUs) | Employees | Stock Incentive Plan 2011 |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |
Stock units, Granted |  |  |  |  |  | 1,253,400 |  |
Stock units, Vesting Period |  |  |  |  | 3 years |  |  |
Stock Options | Stock Incentive Plan 2020 |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |
Percentage of outstanding shares on a fully diluted basis |  |  |  |  |  |  | 5.00% |
Stock options, Granted |  | 278,271 | 3,100,200 |  |  |  |  |
Stock units, Vesting Period |  |  | 4 years |  |  |  |  |
Stock units, Cliff Vesting Period |  |  | 1 year |  |  |  |  |
Stock Options | Stock Incentive Plan 2011 |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |
Stock options, Granted |  |  |  |  |  | 1,875,000 |  |
Stock Options | Employees | Stock Incentive Plan 2011 |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |
Stock units, Vesting Period |  |  |  |  |  | 4 years |  |
Performance-Based RSUs |  |  |  |  |  |  |  |
Stockholders Equity Note [Line Items] |  |  |  |  |  |  |  |
Shares issued, related to the vesting of RSUs | [1] |  |  |  |  |  | 1,923,316 | 1,107,660
Treasury shares for settlement of employee tax obligations |  |  |  |  |  |  | 816,931 | 461,820
[1] | Performance-based RSUs vested in connection with the achievement of certain regulatory and sales performance conditions associated with the REDUCE-IT clinical trial and subsequent revenue growth. These performance-based RSUs have fully vested as of August 2021.

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