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Loans Payable - Schedule of Loans Payable Reported at Fair Value and Measured on Recurring Basis (Details) - USD ($) $ in Thousands | 1 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 | May 31, 2020 | Dec. 31, 2020
Short Term Debt [Line Items] |  |  |
Balance | $ 0 |  |
2020 Notes |  |  |
Short Term Debt [Line Items] |  |  |
Issuance of 2020 Notes and Bridge Loan |  | $ 15,000 |
Conversion of 2020 convertible promissory notes to Series C convertible preferred stock |  | $ (15,900) |
Recurring | Loans Payable |  |  |
Short Term Debt [Line Items] |  |  |
Balance |  |  | $ 0
Change in fair value of loans payable and other adjustments |  |  | 3,053
Balance |  |  | 12,880
Recurring | Loans Payable | 2020 Notes and Bridge Loan |  |  |
Short Term Debt [Line Items] |  |  |
Issuance of 2020 Notes and Bridge Loan |  |  | 16,800
Recurring | Loans Payable | Lilly Asia Ventures Option Exercise |  |  |
Short Term Debt [Line Items] |  |  |
Issuance of repurchase payable for the Lilly Asia Ventures option exercise |  |  | 10,771
Recurring | Loans Payable | Bridge Loan |  |  |
Short Term Debt [Line Items] |  |  |
Issuance of loans payable for conversion settlement of the Bridge Loan |  |  | 2,109
Recurring | Loans Payable | Series C convertible preferred stock | Bridge Loan |  |  |
Short Term Debt [Line Items] |  |  |
Conversion of 2020 convertible promissory notes to Series C convertible preferred stock |  |  | (2,163)
Recurring | Loans Payable | Series C convertible preferred stock | 2020 Notes |  |  |
Short Term Debt [Line Items] |  |  |
Conversion of 2020 convertible promissory notes to Series C convertible preferred stock |  |  | $ (17,690)

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