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Represents the maximum amount of payments receivable under the agreement.

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Represents the amount of near-term payments that can be received under the agreement.

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The maximum percentage of gross margins of sales of the drug received as royalties under the collaborative arrangement.

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Represents the next prospective milestone payment to be earned.

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

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The portion of upfront fees received during the period under the terms of the agreement that are recognized as revenue during the period.

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No definition available.

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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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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 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.

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Collaborative Arrangements and Licensing Agreements, Traditional Pharmaceutical Alliances and Licensing - Bayer HealthCare (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended			9 Months Ended
	May. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue earned		$ 49,121		$ 44,063	$ 232,133	$ 129,300
Bayer HealthCare [Member] \| Collaborations and Licensing Agreements [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue earned		1,000			92,400
Deferred revenue		$ 7,600			$ 7,600
Bayer HealthCare [Member] \| Collaborations and Licensing Agreements [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage		2.00%			40.00%
Bayer HealthCare [Member] \| Agreement Entered into in May 2015 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Near-term payments	$ 155,000
Upfront fee received			$ 100,000
Next prospective milestone		$ 55,000			$ 55,000
Bayer HealthCare [Member] \| Agreement Entered into in May 2015 [Member] \| Minimum [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Percentage of gross margins of sales received as royalties	20.00%
Bayer HealthCare [Member] \| Agreement Entered into in May 2015 [Member] \| License Fees, Substantive Milestone Payments and Other Payments [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable		375,000			375,000
Bayer HealthCare [Member] \| Agreement Entered into in May 2015 [Member] \| Development Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable		120,000			120,000
Bayer HealthCare [Member] \| Agreement Entered into in May 2015 [Member] \| Commercialization Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable		$ 110,000			$ 110,000
Bayer HealthCare [Member] \| Agreement Entered into in May 2015 [Member] \| ISIS-FXI [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront fee recognized			91,200
Bayer HealthCare [Member] \| Agreement Entered into in May 2015 [Member] \| ISIS-FXI Development Activities [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront fee recorded as deferred revenue			$ 8,800