No definition available.

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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.

+ Details

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- Definition

Represents the maximum amount of payments receivable under the agreement.

+ References

No definition available.

+ Details

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- Definition

Represents the number of active collaborations with the collaborative partner.

+ References

No definition available.

+ Details

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- Definition

Represents the next prospective milestone payment to be earned.

+ 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)

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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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- Definition

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

+ References

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=19771982&loc=SL6892177-166501

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Collaborative Arrangements and Licensing Agreements, Traditional Pharmaceutical Alliances and Licensing - Biogen Idec (ISIS-SMN) (Details) - Biogen Idec [Member] $ in Millions	1 Months Ended		6 Months Ended
	Jul. 31, 2015 USD ($)	Jan. 31, 2012 USD ($)	Jun. 30, 2015 USD ($) Agreement
ISIS-SMN [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Cumulative payments received			$ 110.0
Next prospective milestone			11.0
ISIS-SMN [Member] \| Phase 3 Study in Infants with SMA [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Milestone payment earned			9.0
ISIS-SMN [Member] \| Open-Label Extension Study in Children with SMA [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Milestone payment earned			7.0
ISIS-SMN [Member] \| Phase 3 Study in Infants and Phase 2 Study in Children with SMA [Member] \| Subsequent Event [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Milestone payment earned	$ 10.7
ISIS-SMN [Member] \| License Fee and Substantive Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable			346.0
ISIS-SMN [Member] \| Development Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable			121.0
ISIS-SMN [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 collaborative agreements \| Agreement			4
Agreement Entered into in January 2012 [Member] \| ISIS-SMN [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront fee recorded as deferred revenue		$ 29.0