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Commitments and Contingencies - Narrative (Details) - USD ($) | 3 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023 | Dec. 31, 2023 | Jun. 30, 2022
Lessee, Lease, Description [Line Items] |  |  |  |  |  |
Impairment (loss) gain | $ 0 | $ 200,000 | $ 200,000 | $ 7,100,000 |  |
Additional milestone payments, contingent amount |  |  | 2,600,000 |  |  |
Milestone contingent amount payable |  |  | 3,400,000 |  |  |
Restructuring Plan |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |
Restructuring charges | 700,000 |  | 1,400,000 |  |  |
Contract Terminations | Restructuring Plan |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |
Restructuring charges | 15,000 | $ 0 | 546,000 | $ 1,888,000 |  |
Non Cancelable Purchase Commitments with Contract Research Organizations | Contract Terminations | Restructuring Plan |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |
Restructuring charges |  |  | 3,200,000 |  | $ 3,100,000 |
Secured Mortgage Loan |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |
Repayments of debt |  |  |  |  | 600,000 |
Secured Mortgage Loan | Loans Payable |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |
Initial principal amount | 82,837,000 |  | 82,837,000 |  | 82,837,000 | $ 52,100,000
Debt issuance costs | 911,000 |  | $ 911,000 |  | 1,410,000 |
Basis interest |  |  | 5.25% |  |  |
Covenant, minimum net worth | $ 85,000,000 |  | $ 85,000,000 |  | $ 85,000,000 |
Minimum |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |
Original lease terms | 2 years |  | 2 years |  |  |
Maximum |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |
Original lease terms | 5 years |  | 5 years |  |  |
Maximum | Secured Mortgage Loan | Loans Payable |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |
Additional future principal (upto) |  |  |  |  |  | $ 32,900,000

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