License and Collaboration Agreements - Summary of Accounts Receivables (Detail) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Current accounts receivable:
Other unbilled	$ 22	$ 19
Current accounts receivable	8,536	26,379
Non-current accounts receivable:
Other unbilled	450	454
Non-current accounts receivable	450	2,312
Total accounts receivable	8,986	28,691
Other [Member]
Current accounts receivable:
Billed to customers	1,173	557
Novartis Royalties [Member]
Current accounts receivable:
Unbilled	5,244	23,806
Nippon Shinyaku Services [Member]
Current accounts receivable:
Unbilled	$ 2,097	1,997
Non-current accounts receivable:
Unbilled		$ 1,858

Other unbilled receivables current.

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Amount, after allowance for credit loss, of accounts and financing receivable. Includes, but is not limited to, notes and loan receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(5))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as noncurrent.

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Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 912
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-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478345/912-310-45-2

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The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481372/852-10-55-10

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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