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Commitments and Contingencies - Additional Information (Details) $ in Thousands	1 Months Ended								3 Months Ended
	Mar. 31, 2025 USD ($)	Jan. 31, 2025 USD ($) ft² Option	Dec. 31, 2023 USD ($) ft²	Jan. 31, 2022 USD ($)	Sep. 30, 2021 ft²	Jun. 30, 2021 ft²	Dec. 31, 2018 USD ($) ft² Option	Aug. 31, 2018 USD ($) ft²	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2024 USD ($)	Apr. 01, 2022 USD ($)	Dec. 31, 2021 USD ($)
Commitments And Contingencies [Line Items]
Area of space subject to operating lease | ft²		7,581					2,485	23,000
Operating lease term		3 years					3 years	3 years
Operating lease cost per year		$ 700					$ 200	$ 900
Annual base rent increase percentage for operating lease		2.00%					2.50%	3.00%
Operating lease commencement date		Jul. 01, 2025					May 01, 2019	Dec. 10, 2018
Operating lease right-of-use assets	$ 3,831								$ 3,831		$ 4,345
Operating lease liabilities	$ 5,950								5,950
Number of options to renewal operating lease term | Option		2					1
Operating lease, renewal term		3 years					2 years
Biogen International GmbH
Commitments And Contingencies [Line Items]
License and collaboration agreement liability				$ 8,200
Southampton Agreement
Commitments And Contingencies [Line Items]
Expenses related to reimbursable patent costs									50	$ 30
Payment for license and collaboration agreement									700
ASU 2016-02
Commitments And Contingencies [Line Items]
Operating leases expense									700	$ 700
Lease Commencement on December 15, 2021
Commitments And Contingencies [Line Items]
Area of space subject to operating lease | ft²					23,000
Operating lease term					3 years
Operating lease commencement date					Dec. 15, 2021
Operating lease expiration date					Dec. 31, 2024
Operating lease right-of-use assets													$ 3,500
Operating lease liabilities													3,500
Lease Commencement on April 2022
Commitments And Contingencies [Line Items]
Area of space subject to operating lease | ft²					15,000
Operating lease commencement date					Apr. 01, 2022
Operating lease expiration date					Dec. 31, 2024
Operating lease right-of-use assets												$ 1,800
Operating lease liabilities												$ 1,800
Lease Extension End Date April 30, 2025
Commitments And Contingencies [Line Items]
Area of space subject to operating lease | ft²						2,485
Operating lease term						3 years
Operating lease commencement date						May 01, 2022
Operating lease expiration date	Jun. 30, 2025					Apr. 30, 2025
Operating lease right-of-use assets													700
Operating lease liabilities													700
Operating lease, renewal term						2 years
Area of additional space subject to operating lease | ft²						2,357
Additional operating lease commencement date						Jul. 06, 2021
Additional operating lease expiration date						Apr. 30, 2025
Additional operating lease, right-of-use asset													800
Additional operating lease, liabilities													$ 800
Operating lease, option to extend						The amended lease provides the Company with the option to extend the term of the lease for an additional two years.
Operating lease, existence of option to extend [true false]						true
Lease Commencement on January 1, 2025
Commitments And Contingencies [Line Items]
Area of space subject to operating lease | ft²			38,000
Operating lease term			2 years
Operating lease commencement date			Jan. 01, 2025
Operating lease expiration date			Dec. 31, 2026
Operating lease right-of-use assets	$ 0		$ 4,100						$ 0
Operating lease liabilities			$ 4,100

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

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
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-Section 50
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-Topic 842
-SubTopic 20
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-Section 45
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