The amount of additional consideration based on net sales of product as defined under a collaboration agreement.

No definition available.

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- Definition

Amount of aggregate consideration receivable under collaborative arrangement excluding drug product revenue.

+ References

No definition available.

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- Definition

Represents the amount of milestone payments related to commercial sales under the collaborative agreement.

+ References

No definition available.

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- Definition

Represents the potential amount of milestone payments related to development and regulatory approval under the collaborative agreement.

+ References

No definition available.

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Estimated joint development extended service period.

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No definition available.

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- Definition

Represents the percentage of costs that will be funded by the other party under a collaborative agreement for development costs.

+ References

No definition available.

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Represents the total potential amount of milestone payments related to development, regulatory approval and commercial sales under the collaborative agreement.

+ References

No definition available.

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- Definition

Represents the amount of fixed and determinable non-contingent upfront payments included under the collaborative agreement as arrangement consideration.

+ References

No definition available.

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Transaction price allocated to performance obligations.

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

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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The value of the noncash (or part noncash) consideration given (for example, liability, equity) in a transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of a transaction not resulting in cash receipts or cash payments in the period.

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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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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Amount of consideration paid in advance for supplies that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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Collaboration Agreements and Revenues - Astellas Agreements - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended				3 Months Ended		12 Months Ended			35 Months Ended	45 Months Ended
	Dec. 31, 2020	Sep. 30, 2019	Apr. 30, 2006	Jun. 30, 2005	Jun. 30, 2020	Jun. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Feb. 28, 2009	Feb. 28, 2009	Jun. 30, 2019
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Total revenue							$ 176,319	$ 256,577	$ 212,958
Unbilled contract asset	$ 2,147						2,147	180,000
Drug Product Revenue [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Total revenue							$ 8,906	(36,324)	64,776
Japan [Member] \| Drug Product Revenue [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Total revenue					$ 8,200				64,800
Europe [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Unbilled contract asset					130,000
Astellas Agreement [Member] \| Japan [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront, non-contingent and time-based payments received											$ 40,100
Potential milestone payments	15,000	$ 12,500		$ 132,500
Commercial sales milestone				15,000
Additional consideration based on net sales description							the low 20% range of the list price
Aggregate considerations received excluding drug product revenue	105,100						$ 105,100
Transaction price and allocated to performance obligations	15,000	$ 12,500					15,000
Consideration associated with milestone included in transaction price						$ 15,000
Astellas Agreement [Member] \| Japan [Member] \| Drug Product Revenue [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Total revenue							$ 4,300	(36,300)	$ 64,800
Astellas Agreement [Member] \| Japan [Member] \| Clinical and Development Milestone [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential milestone payments				22,500
Astellas Agreement [Member] \| Japan [Member] \| Regulatory Milestone [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential milestone payments				$ 95,000
Astellas Agreement [Member] \| Europe [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront, non-contingent and time-based payments received										$ 320,000
Additional consideration based on net sales description							low 20% range
Aggregate considerations received excluding drug product revenue	540,000						$ 540,000
Transaction price and allocated to performance obligations												$ 130,000
Development and regulatory approval milestones			$ 425,000
Percentage of joint development costs committed to fund			50.00%
Revenue during period from performance obligations	$ 800						$ 800	128,800
Unbilled contract asset								$ 130,000
Milestone payment received					$ 130,000
Estimated joint development extended service period							2024
Astellas Agreement [Member] \| Europe [Member] \| Clinical and Development Milestone [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential milestone payments			$ 90,000
Astellas Agreement [Member] \| Europe [Member] \| Regulatory Milestone [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential milestone payments			$ 335,000