No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The number of programs under which drugs are to be developed and commercialized under the collaboration agreement.

+ References

No definition available.

+ Details

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- Definition

The number of separate performance obligations under the collaboration agreement.

+ References

No definition available.

+ Details

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- Definition

The amount of consideration the Company is eligible to earn under the collaboration agreement, including any variable consideration.

+ References

No definition available.

+ Details

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- Definition

The amount of upfront payments received during the period under the collaboration agreement.

+ References

No definition available.

+ Details

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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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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Collaborative Arrangements and Licensing Agreements, Janssen Biotech, Inc. (Details) $ in Thousands	1 Months Ended					12 Months Ended			17 Months Ended
	Jan. 31, 2018 USD ($)	Nov. 30, 2017 USD ($)	Jul. 31, 2016 USD ($)	May 31, 2015 USD ($)	Dec. 31, 2014 USD ($) PerformanceObligation Program	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Nov. 30, 2017 USD ($)
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue				$ 91,200		$ 599,674	$ 514,179	$ 372,776
Deferred revenue							233,362
Licensing and Other Royalties [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue						14,755	7,474	21,884
R&D [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue						344,752	394,165	$ 350,009
Janssen Biotech, Inc. [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of programs under which drugs are to be developed and commercialized \| Program					3
Upfront payment received					$ 35,000
Minimum amount of payments receivable for license fees and substantive milestones						800,000
Maximum amount of payments receivable for development milestones						175,000
Maximum amount of payments receivable for regulatory milestones						440,000
Maximum amount of payments receivable for commercialization milestones						180,000
Cumulative payments received						75,000
Next prospective milestone						5,000
Number of separate performance obligations \| PerformanceObligation					1
Transaction price					$ 35,000
Deferred revenue						$ 0	$ 0
Janssen Biotech, Inc. [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage						1.00%	7.00%	7.00%
Janssen Biotech, Inc. [Member] \| Licensing and Other Royalties [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue									$ 15,000
Janssen Biotech, Inc. [Member] \| IONIS-JBI1-2.5 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 5,000		$ 10,000
Janssen Biotech, Inc. [Member] \| IONIS-JBI2-2.5 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		$ 5,000
Janssen Biotech, Inc. [Member] \| R&D [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue						$ 6,600	$ 36,000	$ 24,800