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 payment to be earned under the collaboration agreement.

+ References

No definition available.

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- Definition

The number of medicines currently being developed under the collaboration agreement(s).

+ 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	1 Months Ended	3 Months Ended		6 Months Ended
	Apr. 30, 2021 USD ($)	Jun. 30, 2021 USD ($) Medicine	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) Medicine	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		$ 125,750	$ 145,537	$ 237,357	$ 278,905
SPINRAZA Royalties [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		72,168	71,746	132,154	137,754
R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		$ 39,889	55,803	$ 67,048	105,209
Biogen [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of medicines currently being developed \| Medicine		8		8
Cumulative payments received		$ 3,000,000		$ 3,000,000
Revenue		100,000	$ 97,700	178,100	$ 185,200
Deferred revenue		$ 429,900		$ 429,900		$ 465,800
Biogen [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage		80.00%	67.00%	75.00%	66.00%
Biogen [Member] \| SPINRAZA Royalties [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		$ 72,200	$ 71,700	$ 132,200	$ 137,800
Biogen [Member] \| R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		27,800	$ 26,000	45,900	$ 47,400
2013 Strategic Neurology [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Next prospective payment		8,000		$ 8,000
2013 Strategic Neurology [Member] \| ION541 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 10,000	$ 10,000