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Estimated amount of reimbursement payable for services provided by Contract Research Organizations (CROs).

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The duration of material rights exercised or expired.

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Number of material rights associated with future payments.

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Amount of allocated determined transaction price under revenue recognition arrangement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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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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Significant agreements - Ionis Accounting Analysis (Details) $ in Thousands		1 Months Ended				12 Months Ended
	Jul. 09, 2021 USD ($)	Jul. 31, 2025 USD ($)	Apr. 30, 2023 USD ($)	Dec. 31, 2021 USD ($)	Jan. 31, 2021 USD ($)	Dec. 31, 2025 USD ($) item	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Jun. 30, 2025 USD ($)
Significant agreements.
Collaboration revenue						$ 72,586	$ 35,275	$ 26,976
Deferred revenue						38,469	101,658	135,194
Ionis
Significant agreements.
Estimated amount payable to CROs	$ 600						400	600
Transaction price	38,000	$ 39,800					37,800		$ 37,800
Payment received	31,000
Collaboration revenue		$ 2,000				2,000	8,881	10,734
Deferred revenue						$ 3,840	$ 3,587	$ 12,464
Number of material rights associated with future payments \| item						4
Ionis \| Maximum
Significant agreements.
Material rights exercise period						7 years
Ionis \| Ionis Share Purchase Agreement
Significant agreements.
Transaction price	3,400
Ionis Evaluation and Option Agreement
Significant agreements.
Payment received	$ 3,000				$ 3,000
Amended Ionis
Significant agreements.
Collaboration revenue			$ 800	$ 1,600