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Significant Accounting Policies - Additional Information (Detail) shares in Millions |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Jun. 16, 2021 USD ($) | Sep. 30, 2021 shares | Sep. 30, 2020 shares | Sep. 30, 2021 Segment shares | Sep. 30, 2020 shares
Accounting Policy [Line Items] |  |  |  |  |
Number of reportable segment | Segment |  |  |  | 1 |
Anti-dilutive shares outstanding | shares |  | 12.5 | 4.2 | 9.7 | 8.9
Description of payment term |  |  |  | The period between the transfer of control of the promised goods and when the Company receives payment is based on 60-day payment terms. |
Description of sales return |  |  |  | Distributors can request to return product to the Company only due to quality issues or for product purchased within one year prior to the product’s expiration date. |
AstraZeneca Agreements [Member] |  |  |  |  |
Accounting Policy [Line Items] |  |  |  |  |
Profit share percent |  |  |  | 50.00% |
HiFiBiO Agreement [Member] |  |  |  |  |
Accounting Policy [Line Items] |  |  |  |  |
Initial upfront payment | $ 25,000,000.0 |  |  |  |
Maximum additional future option, clinical, regulatory, and commercial milestone payments | 1,100,000,000 |  |  |  |
Contingent consideration | $ 0 |  |  |  |

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