License Agreements - Hangzhou Highlightll Pharmaceutical Agreement (Details) - USD ($)	1 Months Ended	3 Months Ended
Mar. 31, 2023	Mar. 31, 2023	Mar. 31, 2022
License and other agreements
Research and development		$ 63,461,000	$ 70,096,000
Highlightll Pharmaceutical Co, Ltd.
License and other agreements
Research and development		0	$ 0
Highlightll Pharmaceutical Co, Ltd. \| License agreement \| Collaborative arrangement
License and other agreements
Payment obligation for license agreement	$ 10,000	$ 10,000
Obligation for issuance of common shares as payment for assets (in shares)	721,136	721,136
Obligation for issuance of common shares as payment for assets, value	$ 10,000,000	$ 10,000,000
Milestone payment due upon achievement of specified developmental, regulatory and commercial milestones, first indication	200,000,000
Milestone payment due upon achievement of specified developmental, regulatory and commercial milestones, second indication	100,000,000
Milestone payment due upon achievement of specified sales-based milestones	$ 650,000,000

Collaborative Arrangement, Obligation for Payments to Acquire Intangible Assets

No definition available.

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- Definition

Collaborative Arrangement, Obligation for Stock Issuable, Shares, Purchase of Assets

+ References

No definition available.

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- Definition

Collaborative Arrangement, Obligation for Stock Issuable, Value, Purchase of Assets

+ References

No definition available.

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- Definition

Milestone Payment To Be Paid By Company Upon Specified Developmental, Regulatory And Commercial Milestone Achievement, First Indication

+ References

No definition available.

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Milestone Payment To Be Paid By Company Upon Specified Developmental, Regulatory And Commercial Milestone Achievement, Second Indication

+ References

No definition available.

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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

No definition available.

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- Definition

The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 912
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-Publisher FASB
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