Percentage of beneficial ownership of any voting securities of the company or any subsidiary or affiliate.

No definition available.

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- Definition

Percentage of expenses for co-promotion of sales and medical affairs.

+ References

No definition available.

+ Details

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- Definition

Maximum dollar amount of milestone payments eligible to be received under a collaboration arrangement.

+ References

No definition available.

+ Details

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- Definition

Range of percentage rates for royalties received on ex-U.S. net sales, as defined by collaboration agreement.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 13.A.4(a).Q1)
-URI http://asc.fasb.org/extlink&oid=27012821&loc=d3e214044-122780

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 13
-Section A

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- Details

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- Details

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- Details

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Collaboration Agreement - Collaboration Agreements with Astellas - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2016	Dec. 31, 2009
Collaborative agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Co-promotion of sales and medical affairs percentage	50.00%
Astellas Pharma Inc. [Member] \| Up-front cash payment arrangement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Non-refundable, upfront cash payment		$ 110,000,000
Astellas Pharma Inc. [Member] \| Development milestone payments [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible to receive milestone payments	$ 335,000,000
Astellas Pharma Inc. [Member] \| Sales milestone payments [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Eligible to receive milestone payments	$ 320,000,000
Astellas Pharma Inc. [Member] \| Collaborative agreement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Range of percentage rates for royalties received on ex-U.S. net sales, as defined by collaboration agreement	Low teens to the low twenties
Astellas Pharma Inc. [Member] \| Collaborative agreement [Member] \| Minimum [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Beneficial ownership percentage of voting securities	5.00%