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Co-Promotion Agreement - Additional Information (Detail) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 | Dec. 31, 2018 | Dec. 31, 2019
Co Promotion Agreement [Line Items] |  |  |
Accrued expenses and other current liabilities | $ 189,650 |  | $ 139,826
Co-Promotion Agreement | Kowa Pharmaceuticals America, Inc. |  |  |
Co Promotion Agreement [Line Items] |  |  |
Agreement amended year | 2017 |  |
Promotion fee as a percentage of gross margin |  | 18.50% |
Maximum co-promotion tail payments receive period | 3 years |  |
Co-promotion tail payments receivable |  | $ 17,800 |
Accrued co- promotion tail payments |  | $ 16,600 |
Accrued expenses and other liabilities | $ 5,200 |  | 10,000
Accrued expenses and other current liabilities | $ 3,900 |  | $ 6,500

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- Definition Accrued co promotion tail payments. + References No definition available. + Details
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- Definition Co-promotion agreement. + References No definition available. + Details
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- Definition Maximum co-promotion tail payments receive period. + References No definition available. + Details
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- Details
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- Details
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