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- Definition

Cumulative amount of payments received under the collaborative arrangement as of the end of the reporting period.

+ References

No definition available.

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Represents the maximum amount of payments receivable under the agreement.

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- Definition

Represents the number of drugs currently in clinical development by the collaborative partner under the agreement.

+ References

No definition available.

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- Definition

Represents the number of Phase 2 studies in which the drug is being evaluated.

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No definition available.

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Represents the number of active collaborations with the collaborative partner.

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No definition available.

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- Definition

Represents the next prospective milestone payment to be earned.

+ References

No definition available.

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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

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

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The amount of consideration recognized during the period for the milestone or milestones.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 28

-Section 50

-Paragraph 2

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=51671726&loc=SL6892177-166501

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Collaborative Arrangements and Licensing Agreements, Traditional Pharmaceutical Alliances and Licensing - Biogen Idec (Nusinersen (formerly ISIS-SMN)) (Details) - Biogen Idec [Member] $ in Millions	1 Months Ended		9 Months Ended
	Oct. 31, 2015 USD ($)	Jan. 31, 2012 USD ($)	Sep. 30, 2015 USD ($) Agreement Drug Study
Nusinersen [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Cumulative payments received			$ 120.0
Next prospective milestone			2.0
Nusinersen [Member] \| Studies in Infants and Children with SMA [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Milestone payment earned			26.7
Nusinersen [Member] \| Open-Label Extension Study for Phase 3 Studies in Infants and Children with SMA [Member] \| Subsequent Event [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Milestone payment earned	$ 11.0
Nusinersen [Member] \| License Fee and Substantive Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable			346.0
Nusinersen [Member] \| Development Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable			121.0
Nusinersen [Member] \| Regulatory Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable			$ 150.0
Collaborations and Licensing Agreements [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of strategic collaboration agreements \| Agreement			4
Collaborations and Licensing Agreements [Member] \| Drugs to Treat Neurological Disorders Under Collaborations [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of drugs currently in development \| Drug			4
Collaborations and Licensing Agreements [Member] \| Drugs to Treat Undisclosed Neurodegenerative Diseases [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of drugs currently in development \| Drug			2
Agreement Entered into in January 2012 [Member] \| Phase 2 Studies in Infants and Children with SMA [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of Phase 2 studies in which drug is being evaluated \| Study			2
Agreement Entered into in January 2012 [Member] \| Phase 2 Studies in Infants with SMA [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of Phase 2 studies in which drug is being evaluated \| Study			1
Agreement Entered into in January 2012 [Member] \| Phase 2 Studies in Children with SMA [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of Phase 2 studies in which drug is being evaluated \| Study			1
Agreement Entered into in January 2012 [Member] \| Nusinersen [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront fee recorded as deferred revenue		$ 29.0