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 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 amount of payments received during the period for advancing programs under the collaboration agreement.

+ References

No definition available.

+ Details

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- Definition

The number of new performance obligations identified 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.

+ Details

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- Definition

The royalty percentage received on gross margins of drug(s) under the collaborative arrangement.

+ 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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- Definition

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, Bayer (Details) $ in Thousands	1 Months Ended		3 Months Ended	12 Months Ended
	Feb. 28, 2017 USD ($) PerformanceObligation	May 31, 2015 USD ($) PerformanceObligation	Jun. 30, 2015 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
R&D [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue				344,752	394,165	$ 350,009
Bayer [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Deferred revenue				$ 4,300	$ 9,300
Bayer [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage				1.00%	13.00%	1.00%
Bayer [Member] \| R&D [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue				$ 5,000	$ 67,100	$ 5,400
Bayer [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront payment received		$ 100,000	$ 100,000
Maximum amount of payments receivable for license fees and substantive milestones				385,000
Maximum amount of payments receivable for development milestones				125,000
Maximum amount of payments receivable for commercialization milestones				$ 110,000
Royalty percentage received on gross margins of both drugs combined				20.00%
Cumulative payments received				$ 175,000
Next prospective milestone				$ 10,000
Number of separate performance obligations \| PerformanceObligation		3
Transaction price		$ 100,000
Bayer [Member] \| IONIS-FXI [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Transaction price		91,200
Bayer [Member] \| R&D Services for IONIS-FXI [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Transaction price		4,300
Bayer [Member] \| IONIS-FXI API [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Transaction price		$ 4,500
Bayer [Member] \| R&D Services for IONIS-FXI-L [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Transaction price	$ 10,100
Bayer [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Payment received for advancing programs	$ 75,000
Number of separate performance obligations \| PerformanceObligation	3
Transaction price	$ 75,000
Number of new performance obligations \| PerformanceObligation	2
Bayer [Member] \| IONIS-FXI-L [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Transaction price	$ 64,900
Number of new performance obligations \| PerformanceObligation	1
Bayer [Member] \| R&D Services for IONIS-FXI-L [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of new performance obligations \| PerformanceObligation	1