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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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The next payment to be achieved under the collaboration agreement.

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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) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 133,814		$ 144,207	$ 478,562	$ 463,142
Biogen [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	80,291		$ 94,695	277,686	$ 262,599
Deferred contract revenue	$ 226,400			$ 226,400		$ 307,400
Biogen [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage	60.00%		66.00%	58.00%	57.00%
Biogen [Member] \| Minimum [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Cumulative payments received	$ 4,000,000			$ 4,000,000
2013 Strategic Neurology [Member] \| QALSODY [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Next payment to be achieved	10,000			10,000
Revenue		$ 20,000
2012 Neurology [Member] \| ION582 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		$ 30,000
2012 Neurology [Member] \| IONIS-MAPT [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Next payment to be achieved	25,000			25,000
2018 Strategic Neurology [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Next payment to be achieved	15,000			$ 15,000
Revenue	$ 7,500