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.

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No definition available.

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- Definition

The amount of milestone payments received during the period under the collaboration agreement.

+ References

No definition available.

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- Definition

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

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No definition available.

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- Definition

The number of medicines currently in development under collaborations.

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No definition available.

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The number of milestone payments achieved during the period under the collaboration agreement.

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No definition available.

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- Definition

The number of new targets advanced during the period under the collaboration agreement.

+ References

No definition available.

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- Definition

Total payments received since inception of the collaboration agreement included in the transaction price for the performance obligation.

+ References

No definition available.

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- Definition

The total amount of the upfront payment received, including the purchase of shares of the Company's stock, under the collaboration agreement.

+ References

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, Biogen (Details) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2019 USD ($) Medicine	Jun. 30, 2019 USD ($) Target Payment	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) Medicine	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 167,892		$ 145,395		$ 628,918	$ 407,559
SPINRAZA Royalties [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	81,672		70,010		211,884	167,743
R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 72,193		62,639		$ 376,833	225,584
Biogen [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of medicines currently in development under collaborations \| Medicine	8				8
Cumulative payments received	$ 2,300,000				$ 2,300,000
Revenue	107,200		$ 104,800		293,800	$ 234,600
Deferred revenue	$ 532,400				$ 532,400		$ 580,900
Biogen [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage	64.00%		72.00%		47.00%	58.00%
Biogen [Member] \| SPINRAZA Royalties [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 81,700		$ 70,000		$ 211,900	$ 167,700
Biogen [Member] \| R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	25,500		$ 34,800		81,900	$ 66,900
2018 Strategic Neurology [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront payment received				$ 1,000,000
Number of milestone payments achieved \| Payment		2
Milestone payment received		$ 7,500
Number of new targets advanced \| Target		2
Next prospective milestone	7,500				7,500
2018 Strategic Neurology [Member] \| R&D Services [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Payments included in transaction price for performance obligation	582,000				582,000
2013 Strategic Neurology [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	(16,500)
Payments included in transaction price for performance obligation	145,000				145,000
2013 Strategic Neurology [Member] \| IONIS-LRRK2 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	8,000
2012 Neurology [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	6,300
Milestone payment received		$ 7,500
Next prospective milestone	10,000				10,000
2012 Neurology [Member] \| R&D Services [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Payments included in transaction price for performance obligation	40,000				40,000
2012 Neurology [Member] \| IONIS-MAPT [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Payments included in transaction price for performance obligation	$ 25,500				$ 25,500