No definition available.

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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

Number of targets advanced 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	1 Months Ended	3 Months Ended			6 Months Ended
	Jul. 31, 2022 USD ($)	Jun. 30, 2022 USD ($)	Mar. 31, 2022 USD ($) Target	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		$ 133,791		$ 125,750	$ 275,710	$ 237,357
SPINRAZA Royalties [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		59,627		72,168	113,444	132,154
R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		55,607		39,889	125,242	67,048
Biogen [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Cumulative payments received		3,300,000			3,300,000
Revenue		76,900		$ 100,000	170,800	$ 178,100
Deferred revenue		$ 368,300			$ 368,300		$ 407,500
Biogen [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage		58.00%		80.00%	62.00%	75.00%
Biogen [Member] \| SPINRAZA Royalties [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		$ 59,600		$ 72,200	$ 113,400	$ 132,200
Biogen [Member] \| R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		$ 17,300		$ 27,800	$ 57,400	$ 45,900
2013 Strategic Neurology [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue			$ 18,000
Number of targets advanced \| Target			2
2013 Strategic Neurology [Member] \| Subsequent Event [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 9,000
2013 Strategic Neurology [Member] \| Maximum [Member] \| Plan [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Next prospective payment	$ 10,000