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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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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482913/230-10-50-8

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Section S99
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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-Section 50
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(17))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
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-SubTopic 210
-Topic 954
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480632/954-210-45-5

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-SubTopic 10
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-Section 50
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