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Summary of Significant Accounting Policies - Schedule of Compensating Balance Arrangements (Detail) - USD ($) $ in Thousands | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Cash and Cash Equivalents [Line Items] |  |
Restricted Cash | $ 777 | $ 1,032
Restricted cash, current (included within prepaid expenses and other current assets) | 0 | 250
Total restricted cash | 777 | 782
Letter of Credit | Waltham Lease |  |
Cash and Cash Equivalents [Line Items] |  |
Restricted Cash | 0 | 250
Letter of Credit | Vienna Austria Lease |  |
Cash and Cash Equivalents [Line Items] |  |
Restricted Cash | 206 | 211
Letter of Credit | Allston Lease Agreement |  |
Cash and Cash Equivalents [Line Items] |  |
Restricted Cash | $ 571 | $ 571

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