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.

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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.

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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.

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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.

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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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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				3 Months Ended		6 Months Ended		17 Months Ended
	Jan. 31, 2018 USD ($)	Nov. 30, 2017 USD ($)	Jul. 31, 2016 USD ($)	Dec. 31, 2014 USD ($) PerformanceObligation Program	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Nov. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue					$ 117,747	$ 112,273	$ 262,165	$ 228,073
Deferred revenue										$ 233,362
Licensing and Other Royalties [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue					545	1,322	1,487	3,912
R&D [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue					60,549	$ 88,585	162,944	$ 196,584
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		800,000
Maximum amount of payments receivable for development milestones					175,000		175,000
Maximum amount of payments receivable for regulatory milestones					440,000		440,000
Maximum amount of payments receivable for commercialization milestones					180,000		180,000
Cumulative payments received					72,000		72,000
Next prospective milestone					5,000		5,000
Number of separate performance obligations \| PerformanceObligation				1
Transaction price				$ 35,000
Deferred revenue					$ 0		$ 0			$ 0
Janssen Biotech, Inc. [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage					5.00%	11.00%	2.00%	6.00%
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					$ 5,500	$ 12,200	$ 5,700	$ 14,700