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The number of therapeutic programs with exclusive license rights under the collaboration agreement.

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The number of therapeutic targets granted to the partner under the collaboration agreement.

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The number of unnamed therapeutic targets granted by the partner under the collaboration agreement.

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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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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Collaborative Arrangements and Licensing Agreements, Alnylam Pharmaceuticals, Inc. (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2015 Program Target
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 787,647	$ 587,367	$ 810,456
R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	479,056	284,009	$ 468,061
Alnylam [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of therapeutic programs \| Program				4
Number of therapeutic targets granted to Ionis \| Target				4
Number of unnamed therapeutic targets granted to Ionis \| Target				2
Number of therapeutic targets granted by Ionis \| Target				4
Deferred revenue	$ 0	$ 0
Alnylam [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage	4.00%	4.00%	0.00%
Alnylam [Member] \| R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 28,426	$ 21,389	$ 0