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Represents the amount of milestone payment to be paid by the company upon the achievement of specified regulatory milestones and annual royalty payments based on net sales of products from patents.

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Represents the amount of milestone payment to be paid by the company upon the achievement of specified regulatory milestones and annual royalty payments based on net sales of products from patents other than the specified product.

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Royalty Payment To Be Paid By Company Upon Specified Approved Products By Net Sales, Percentage

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The cash outflow to acquire asset without physical form usually arising from contractual or other legal rights, excluding goodwill.

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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.

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Number of shares of stock issued during the period as part of a transaction to acquire assets that do not qualify as a business combination.

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Value of shares of stock issued during the period as part of a transaction to acquire assets that do not qualify as a business combination.

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License Agreements - AstraZeneca License Agreement (Details) - USD ($)	1 Months Ended		3 Months Ended
	Sep. 30, 2018	Oct. 31, 2016	Mar. 31, 2023	Mar. 31, 2022
License and other agreements
Milestone payment to be paid upon regulatory achievement			$ 567,350,000
Commercial milestone payment to be paid			1,420,450,000
Research and development			63,461,000	$ 70,096,000
AstraZeneca
License and other agreements
Research and development			0	0
AstraZeneca \| Collaborative arrangement
License and other agreements
Research and development			$ 0	$ 0
AstraZeneca \| Collaborative arrangement \| Maximum
License and other agreements
Milestone payment to be paid upon regulatory achievement		$ 30,000,000
Milestone payment to be paid for any product other than rimegepant		60,000,000
Commercial milestone payment to be paid		$ 120,000,000
Royalty percentage	10.00%
Agreement term after first commercial sale		10 years
AstraZeneca \| Collaborative arrangement \| Minimum
License and other agreements
Royalty percentage	0.00%
AstraZeneca \| License agreement
License and other agreements
Payment for license agreement	$ 3,000,000
Issuance of common shares as payment for assets (in shares)	109,523
Issuance of common shares as payment for assets	$ 4,080,000
Milestone payment due upon achievement of specified regulatory and commercial milestones	55,000,000
Milestone payment due upon achievement of specified sales-based milestones	$ 50,000,000
AstraZeneca \| License agreement \| Maximum
License and other agreements
Royalty percentage	10.00%
AstraZeneca \| License agreement \| Minimum
License and other agreements
Royalty percentage	0.00%