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.

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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, Roche (Details) $ in Thousands	1 Months Ended			3 Months Ended			6 Months Ended
	Jan. 31, 2018 USD ($)	Dec. 31, 2016 USD ($)	Apr. 30, 2013 USD ($) PerformanceObligation	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	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
Roche [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				107,000			107,000
Next prospective milestone				10,000			10,000
Number of separate performance obligations \| PerformanceObligation			1
Transaction price			$ 30,000
Deferred revenue				$ 0			$ 0		$ 0
Roche [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage				1.00%	3.00%		1.00%	1.00%
Roche [Member] \| IONIS-HTT [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 45,000
Roche [Member] \| R&D [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue				$ 1,700	$ 2,900	$ (1,600)	$ 3,600	$ 1,400