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Term of the patent, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Potential payments for commercial milestones under a collaboration agreement.

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Potential later stage milestone payments and royalties.

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The amount of potential milestone payments to be paid under a license agreement.

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Research Collaboration Term

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The amount of time required for third party collaborator to give written notice prior to terminating the collaborative agreement.

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Termination Notice Period Before First Commercial Sale

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Upfront payments made under a collaboration agreement.

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Upfront payments received under a collaboration agreement.

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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.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Significant Collaboration and Licensing Agreements - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended					3 Months Ended			9 Months Ended		12 Months Ended	27 Months Ended	28 Months Ended	123 Months Ended
	May 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Mar. 31, 2015	Jun. 30, 2010	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2017	Sep. 30, 2020	Jul. 31, 2020	Apr. 30, 2020
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue from contract with customer						$ 258.5		$ 222.1	$ 798.0	$ 544.0
Takeda \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront payments made															$ 120.0
Potential milestone payments						1,900.0			1,900.0		$ 1,900.0			$ 1,900.0
Idorsia \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront payments made	$ 45.0
Incremental funding provided	$ 7.2
Research collaboration term	2 years
Potential commercial milestone payments						750.0			750.0		750.0			750.0
Collaboration termination notice period	90 days
Idorsia \| Collaborative Arrangement \| NBI-827104
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Potential milestone payments						365.0			365.0		365.0			365.0
Idorsia \| Collaborative Arrangement \| Development Product Candidates
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Potential milestone payments						620.0			620.0		620.0			620.0
Xenon \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration termination notice period		90 days
Voyager \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Termination notice period, before first commercial sale			180 days
Termination notice period, after date of notice			1 year
B I A L \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Potential commercial milestone payments						75.0			$ 75.0		75.0			75.0
Milestone payment																$ 20.0
Minimum sales requirement period									2 years
Mitsubishi Tanabe \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration termination notice period				180 days
Deferred revenue recognized						0.5			$ 1.8		2.6
Deferred revenue, balance						7.6			7.6		7.6			7.6
Upfront payments received				$ 30.0
Revenue from contract with customer												$ 15.0	$ 19.8
Potential milestone payment receipts						70.0			70.0		70.0			70.0
Mitsubishi Tanabe \| Collaborative Arrangement \| Patents \| Minimum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Patent term				10 years
AbbVie \| Collaborative Arrangement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaboration termination notice period					180 days
Revenue from contract with customer					$ 75.0		$ 30.0							165.0
Potential milestone payment receipts						$ 366.0			$ 366.0		$ 366.0			$ 366.0
AbbVie \| Collaborative Arrangement \| Patents \| Minimum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Patent term					10 years