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

+ References

No definition available.

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- Definition

The number of collaboration agreements with the collaboration partner.

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No definition available.

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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	3 Months Ended		12 Months Ended
	Mar. 31, 2019 USD ($) Agreement	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 297,214	$ 144,419
R&D [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 229,126	$ 102,396
Roche [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of collaboration agreements \| Agreement	2
Deferred revenue	$ 67,500		$ 72,600
Roche [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage	14.00%	1.00%
Roche [Member] \| R&D [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 41,200	$ 2,000
Huntington's Disease [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of collaboration agreements \| Agreement	1
Cumulative payments received	$ 220,000
Next prospective milestone	15,000
Huntington's Disease [Member] \| IONIS-HTT [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 35,000		$ 0
IONIS-FB-L for Complement-Mediated Diseases [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of collaboration agreements \| Agreement	1