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 each additional drug developed under the collaboration agreement.

+ 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 license fees and substantive 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 amount of milestone payments received during the period 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 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

Royalty percentage received on the net sales of a drug by a collaboration partner under the collaboration agreement.

+ References

No definition available.

+ Details

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Period Type:	duration

- 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, Roche (Details) $ in Thousands	1 Months Ended			2 Months Ended	3 Months Ended		12 Months Ended
	Oct. 31, 2018 USD ($) PerformanceObligation	May 31, 2015 USD ($)	Apr. 30, 2013 USD ($) PerformanceObligation	Mar. 01, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		$ 91,200					$ 599,674	$ 514,179	$ 372,776
Deferred revenue						$ 233,362		233,362
R&D [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue							344,752	394,165	$ 350,009
Roche [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Deferred revenue					$ 72,600	0	$ 72,600	$ 0
Roche [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage							1.00%	11.00%	3.00%
Roche [Member] \| R&D [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue							$ 8,300	$ 55,700	$ 10,700
Huntington's Disease [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront payment received			$ 30,000
Milestone payments received								$ 3,000
Maximum amount of payments receivable for license fees and substantive milestones					365,000		365,000
Maximum amount of payments receivable for development milestones					70,000		70,000
Maximum amount of payments receivable for regulatory milestones					170,000		170,000
Maximum amount of payments receivable for commercialization milestones					80,000		80,000
Maximum amount of payment receivable for each additional drug developed					136,500		136,500
Cumulative payments received					112,000		112,000
Next prospective milestone					15,000		15,000
Number of separate performance obligations \| PerformanceObligation			1
Transaction price			$ 30,000
Huntington's Disease [Member] \| IONIS-HTT [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue						$ 45,000
Huntington's Disease [Member] \| Subsequent Event [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront payment received				$ 35,000
IONIS-FB-L for Complement-Mediated Diseases [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront payment received	$ 75,000				75,000
Maximum amount of payments receivable for license fees and substantive milestones					684,000		684,000
Next prospective milestone					$ 20,000		$ 20,000
Number of separate performance obligations \| PerformanceObligation	1
Transaction price	$ 75,000
Royalty percentage received on net sales of drug							20.00%