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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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