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Leases - Additional Information (Detail) $ in Thousands		6 Months Ended
	Nov. 11, 2019 USD ($)	Jun. 30, 2024 USD ($) m²	Dec. 31, 2023 USD ($)
Lessee, Lease, Description [Line Items]
Operating lease, liability		$ 3,198
Right-of-use assets		$ 4,872	$ 5,650
Vienna Lease
Lessee, Lease, Description [Line Items]
Office space | m²		1,200
Lease not yet commenced, term of contract		7 years
Annual base rent		$ 282
Allston Lease
Lessee, Lease, Description [Line Items]
Lease not yet commenced	$ 1,100

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-3

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Term of lessee's operating lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-3

+ Details

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Balance Type:	na
Period Type:	instant

X

- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479041/842-20-45-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479041/842-20-45-1

+ Details

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Period Type:	instant

X

- Definition

Lessee, Operating Lease, Lease Not Yet Commenced, Amount

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Lessee, Operating Lease, Lease Not Yet Commenced, Annual Base Rent

+ References

No definition available.

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- Definition

Lessee, Operating Lease, Lease Not Yet Commenced, Office Space

+ References

No definition available.

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- Details

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- Details

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