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Cumulative amount of payments received under the collaboration agreement as of the end of the reporting period.

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No definition available.

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The maximum amount of payments receivable for commercialization milestones under the collaboration agreement.

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No definition available.

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The maximum amount of payments receivable for development milestones under the collaboration agreement.

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No definition available.

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The maximum amount of payments receivable for regulatory milestones under the collaboration agreement.

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No definition available.

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The minimum amount of payments receivable for license fees and substantive milestone payments under the collaboration agreement.

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No definition available.

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The next potential milestone payment to be earned under the collaboration agreement.

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No definition available.

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The number of drugs currently in clinical development under the collaboration agreement.

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

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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, Research, Development and Commercialization Partners - GSK (Details) $ in Thousands	1 Months Ended	3 Months Ended			9 Months Ended
	Mar. 31, 2010 USD ($)	Sep. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) Drug	Sep. 30, 2015 USD ($)
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue earned		$ 110,927		$ 49,121	$ 186,272	$ 232,133
Agreement Entered into in March 2010 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of drugs currently in development \| Drug					5
Upfront payment recorded as deferred revenue	$ 38,000
Minimum amount of payments receivable		1,000,000			$ 1,000,000
Maximum amount of payments receivable for development milestones		168,500			168,500
Maximum amount of payments receivable for regulatory milestones		363,500			363,500
Maximum amount of payments receivable for commercialization milestones		338,000			338,000
Revenue earned		1,200		$ 1,600	8,200	$ 22,400
Deferred revenue		$ 4,700			$ 4,700
Agreement Entered into in March 2010 [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage		1.00%		3.00%	4.00%	10.00%
Agreement Entered into in March 2010 [Member] \| Minimum [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Cumulative payments received		$ 154,000			$ 154,000
Agreement Entered into in March 2010 [Member] \| Maximum [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Next prospective milestone		1,500			1,500
Agreement Entered into in March 2010 [Member] \| IONIS-TTR [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Cumulative payments received		$ 60,000			$ 60,000
Agreement Entered into in March 2010 [Member] \| IONIS-HBV, IONIS-HBV-L, IONIS-GSK4-L, and IONIS-RHO-2.5 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of drugs currently in development \| Drug					4
Agreement Entered into in March 2010 [Member] \| IONIS-HBV and IONIS-HBV-L [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of drugs currently in development \| Drug					2
Agreement Entered into in March 2010 [Member] \| IONIS-HBV-L [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Milestone payment earned			$ 1,500