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Number of plaintiffs that have filed claims pertaining to a loss contingency.

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Legal Proceedings (Details) - John Makris, et al. v. Ionis Pharmaceuticals, Inc., et al. [Member] $ in Millions			3 Months Ended
	Jun. 03, 2022 USD ($)	Aug. 05, 2021 Plaintiff	Sep. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)
Legal Procedings [Abstract]
Number of plaintiffs \| Plaintiff		4
Settlement agreement	$ 12.5
Contribution to settlement agreement by insurance carrier			$ 4.8
Other Expense [Member]
Legal Procedings [Abstract]
Litigation settlement expense				$ 12.5