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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 per drug under the agreement.

+ References

No definition available.

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- Definition

Represents the period from the inception of the collaboration during which a change of control could result in the entity being required to refund the upfront payment received.

+ 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

Represents revenue earned as a percentage of the entity's total revenues.

+ References

No definition available.

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- Definition

Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets 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 SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 10

-Section S99

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-Subparagraph (SAB TOPIC 13.A.4(a).Q1 Response)

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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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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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Collaborative Arrangements and Licensing Agreements, Traditional Pharmaceutical Alliances and Licensing - Biogen Idec (Strategic Neurology) (Details) (USD $)	3 Months Ended		1 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Sep. 30, 2013	Apr. 30, 2015
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue earned	$ 62,583,000us-gaap_Revenues	$ 28,161,000us-gaap_Revenues
Biogen Idec [Member] \| Collaborations and Licensing Agreements [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue earned	39,200,000	10,200,000
Percent of total revenue (in hundredths)	63.00%	36.00%
Deferred revenue	110,800,000
Biogen Idec [Member] \| Agreement Entered into in September 2013 [Member] \| Strategic Neurology [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront fee recorded as deferred revenue			100,000,000
Period during which a change in control could result in requirement to refund upfront payment	6 years
Cumulative payments received	125,000,000
Biogen Idec [Member] \| Agreement Entered into in September 2013 [Member] \| Strategic Neurology [Member] \| Subsequent Event [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Milestone payment earned				10,000,000
Biogen Idec [Member] \| Agreement Entered into in September 2013 [Member] \| Strategic Neurology [Member] \| Maximum [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Next prospective milestone	10,000,000
Biogen Idec [Member] \| Agreement Entered into in September 2013 [Member] \| Strategic Neurology [Member] \| Antisense Drug for Neurological Disease [Member] \| License Fee and Substantive Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payment receivable per drug	260,000,000
Biogen Idec [Member] \| Agreement Entered into in September 2013 [Member] \| Strategic Neurology [Member] \| Antisense Drug for Neurological Disease [Member] \| Research and Development Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payment receivable per drug	60,000,000
Biogen Idec [Member] \| Agreement Entered into in September 2013 [Member] \| Strategic Neurology [Member] \| Antisense Drug for Neurological Disease [Member] \| Regulatory Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payment receivable per drug	130,000,000
Biogen Idec [Member] \| Agreement Entered into in September 2013 [Member] \| Strategic Neurology [Member] \| Other Modalities [Member] \| Pre-specified Events [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payment receivable per drug	90,000,000
Biogen Idec [Member] \| Agreement Entered into in September 2013 [Member] \| Strategic Neurology [Member] \| Other Modalities [Member] \| Research and Development Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payment receivable per drug	35,000,000
Biogen Idec [Member] \| Agreement Entered into in September 2013 [Member] \| Strategic Neurology [Member] \| Other Modalities [Member] \| Regulatory Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payment receivable per drug	$ 55,000,000