v3.25.1

COMMITMENTS AND CONTINGENCIES - Narrative (Details)	1 Months Ended		3 Months Ended
COMMITMENTS AND CONTINGENCIES - Narrative (Details)	Feb. 28, 2021 USD ($) ft²	Mar. 31, 2020 USD ($) ft²	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2024 USD ($)
Schedule Of Asset Acquisition [Line Items]
Operating lease right-of-use assets			$ 3,048,000		$ 3,176,000
Present value of operating lease liabilities			24,089,000		24,900,000
Impairment charge			300,000	$ 6,600,000
Impairment of long-lived assets, right-of-use asset			0	5,000,000
Impairment of leasehold			0	1,600,000
Lease payments			1,500,000	$ 1,400,000
Cambridge, Massachusetts
Schedule Of Asset Acquisition [Line Items]
Lease term (in years)		11 years
Facility size \| ft²		40,514
Annual base rent		$ 4,100,000
Letter of credit		$ 2,000,000.0
Escalating rent payments, percent		3.00%
Tenant improvement allowances		$ 3,700,000
Operating lease right-of-use assets			3,000,000.0		3,200,000
Present value of operating lease liabilities			$ 22,500,000		23,200,000
Remaining lease term (in years)			5 years 11 months
Incremental borrowing rate (as a percent)			8.50%
San Mateo, California
Schedule Of Asset Acquisition [Line Items]
Facility size \| ft²	17,340
Escalating rent payments, percent	3.00%
Operating lease right-of-use assets			$ 0
Present value of operating lease liabilities			$ 1,600,000		$ 1,700,000
Remaining lease term (in years)			1 year 3 months
Incremental borrowing rate (as a percent)			11.18%
Initial annual base rent	$ 1,200,000
Security deposit	$ 100,000

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Lessee, Operating Lease, Escalating Rent Payments, Percent

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Lessee, Operating Lease, Incremental Borrowing Rate

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Lessee, Operating Lease, Initial Annual Base Rent

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Lessee, Operating Lease, Tenant Improvement Allowances

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Schedule Of Asset Acquisition

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Area of a real estate property.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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The adjustment to reduce the value of existing agreements that specify the lessee's rights to use the leased property. This expense is charged when the estimates of future profits generated by the leased property are reduced.

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Remaining lease term of operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Amount of loss from impairment of right-of-use asset from operating lease.

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

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

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The amount of an asset, typically cash, provided to a counterparty to provide certain assurance of performance by the entity pursuant to the terms of a written or oral agreement, such as a lease.

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