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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The number of separate performance obligations under the collaboration agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

The amount of consideration the Company earned or is eligible to earn under the collaboration agreement, including any variable consideration.

+ References

No definition available.

+ Details

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Balance Type:	credit
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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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Data Type:	num:percentItemType
Balance Type:	na
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.

+ References

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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, Roche (Details) $ in Thousands	1 Months Ended		3 Months Ended			12 Months Ended
	Oct. 31, 2018 USD ($) PerformanceObligation	Apr. 30, 2013 USD ($) PerformanceObligation	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue						$ 1,122,599	$ 599,674	$ 514,179
R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue						770,149	344,752	$ 394,165
Roche [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Deferred revenue				$ 72,600		$ 52,300	$ 72,600
Roche [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage						5.00%	1.00%	11.00%
Roche [Member] \| R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue						$ 57,000	$ 8,300	$ 55,700
Huntington's Disease [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront payment received		$ 30,000
Milestone payments received			$ 35,000					$ 3,000
Maximum amount of payments receivable for license fees and milestones						365,000
Maximum amount of payments receivable for development milestones						70,000
Maximum amount of payments receivable for regulatory milestones						170,000
Maximum amount of payments receivable for commercialization milestones						80,000
Maximum amount of payment receivable for each additional drug developed						136,500
Next prospective milestone						15,000
Number of separate performance obligations \| PerformanceObligation		1
Transaction price		$ 30,000
Revenue			$ 35,000		$ 45,000
Huntington's Disease [Member] \| Minimum [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Cumulative payments received						145,000
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 milestones						684,000
Next prospective milestone						$ 20,000
Number of separate performance obligations \| PerformanceObligation	1
Transaction price	$ 75,000
Royalty percentage received on net sales of drug						20.00%