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

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

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No definition available.

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Represents the maximum amount of payments receivable under the agreement.

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No definition available.

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Represents the minimum amount of payments receivable under the agreement.

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No definition available.

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

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No definition available.

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Represents the next prospective milestone payment to be earned.

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No definition available.

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- Definition

Represents the amount of upfront fees received during the period under the agreement.

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No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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

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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.

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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).

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Collaborative Arrangements and Licensing Agreements, Traditional Pharmaceutical Alliances and Licensing - GlaxoSmithKline (Details) - Range [Domain] - Subsequent Event Type [Domain] $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended
	May. 31, 2011 USD ($)	Mar. 31, 2010 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) Drug	Jun. 30, 2014 USD ($)
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue earned			$ 120,428	$ 57,076	$ 183,012	$ 85,237
Glaxo Smith Kline [Member] \| Collaborations and Licensing Agreements [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of drugs currently in development \| Drug					5
Upfront fee received	$ 3,000	$ 35,000
Cumulative payments received			129,500		$ 129,500
Revenue earned			4,300	$ 3,500	20,800	$ 6,800
Deferred revenue			$ 6,200		$ 6,200
Glaxo Smith Kline [Member] \| Collaborations and Licensing Agreements [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage			4.00%		11.00%
Glaxo Smith Kline [Member] \| Collaborations and Licensing Agreements [Member] \| Pre-specified Events [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Minimum amount of payments receivable			$ 1,300,000		$ 1,300,000
Glaxo Smith Kline [Member] \| Collaborations and Licensing Agreements [Member] \| Development Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable			220,500		220,500
Glaxo Smith Kline [Member] \| Collaborations and Licensing Agreements [Member] \| Regulatory Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable			483,500		483,500
Glaxo Smith Kline [Member] \| Collaborations and Licensing Agreements [Member] \| Commercialization Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable			428,000		428,000
Glaxo Smith Kline [Member] \| Collaborations and Licensing Agreements [Member] \| ISIS-TTR [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Cumulative milestone payments earned			60,000		60,000
Glaxo Smith Kline [Member] \| Collaborations and Licensing Agreements [Member] \| ISIS-TTR [Member] \| Development Milestones [Member] \| Phase 2/3 Study [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Next prospective milestone			10,000		10,000
Glaxo Smith Kline [Member] \| Collaborations and Licensing Agreements [Member] \| ISIS-GSK4 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Next prospective milestone			$ 5,000		$ 5,000
Glaxo Smith Kline [Member] \| Collaborations and Licensing Agreements [Member] \| ISIS-HBV, ISIS-GSK4-L, ISIS-RHO-2.5, and ISIS-GSK6-L [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of drugs currently in development \| Drug					4