Lessee operating lease extended term of contract.

No definition available.

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- Definition

Lessee operating lease liability measurement term.

+ References

No definition available.

+ Details

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- Definition

Lessee operating lease number of renewal option.

+ References

No definition available.

+ Details

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- Definition

Operating lease expiration date, month and year.

+ References

No definition available.

+ Details

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- Definition

Potential future milestone payments.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Date which lease or group of leases is set to expire, in YYYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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+ Details

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- Definition

Discount rate used by lessee to determine present value of operating lease payments.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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Period Type:	instant

- Definition

Indicates (true false) whether lessee has option to extend operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 20
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-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

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- Definition

Indicates (true false) whether lessee has option to terminate operating lease.

+ References

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- Definition

Term of lessee's operating lease renewal, 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
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-Section 50
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Period Type:	instant

- Definition

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

+ References

+ Details

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- 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/2009/role/commonPracticeRef
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- Definition

Amount of expense for research and development. Includes, but is not limited to, cost for computer software product to be sold, leased, or otherwise marketed and writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both. Excludes write-down of intangible asset acquired in business combination or from joint venture formation or both, used in research and development activity.

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- Details

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- Details

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- Details

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Commitments and Contingencies - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($) Option	Jun. 30, 2025 USD ($)	Dec. 31, 2025
Loss Contingencies [Line Items]
Research and development expense	$ 900,000	$ 2,000,000	$ 2,100,000	$ 3,700,000
Operating lease discount rate	9.80%		9.80%		9.80%
Licensing Agreements
Loss Contingencies [Line Items]
Research and development expense			$ 0	$ 0
Product Development
Loss Contingencies [Line Items]
Future potential milestone payments	$ 10,000,000.0		10,000,000.0
Development Milestone
Loss Contingencies [Line Items]
Future potential milestone payments	16,500,000		16,500,000
Commercialization Milestone
Loss Contingencies [Line Items]
Future potential milestone payments	$ 16,500,000		$ 16,500,000
U.S
Loss Contingencies [Line Items]
Operating lease term	5 years		5 years
Operating lease expiration date			Jan. 31, 2027
Tokyo, Japan \| Previous Lease Agreement
Loss Contingencies [Line Items]
Lessee, operating lease, existence of option to terminate			true
Tokyo, Japan \| New Lease Agreement
Loss Contingencies [Line Items]
Operating lease term	12 months		12 months
Operating lease number of renewal option \| Option			1
Operating lease liability measurement term			14 months
Operating lease expiration date, month and year			2025-05
Operating lease, auto-renewal term	2 months		2 months
Operating lease, extension term			2 months
Lessee, operating lease, existence of option to extend			true
Operating lease discount rate	6.51%		6.51%