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Co-Promotion Agreement - Additional Information (Detail) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2021 | Dec. 31, 2018 | Dec. 31, 2020
Co Promotion Agreement [Line Items] |  |  |
Accrued expenses and other current liabilities | $ 289,684 |  | $ 198,641
Co-Promotion Agreement | Kowa Pharmaceuticals America, Inc. |  |  |
Co Promotion Agreement [Line Items] |  |  |
Promotion fee as a percentage of gross margin |  | 18.50% |
Maximum co-promotion tail payments receive period | 3 years |  |
Co-promotion tail payments payable |  | $ 17,800 |
Accrued co- promotion tail payments |  | $ 16,600 |
Accrued expenses and other liabilities | $ 1,300 |  | 3,800
Accrued expenses and other current liabilities |  |  | $ 3,200

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- Definition Co promotion tail payments payable. + References No definition available. + Details
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- Details
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- Details
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