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+ References

No definition available.

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 808
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479402/808-10-50-1

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479837/606-10-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-8

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479837/606-10-45-2

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-8

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Significant agreements - Oxurion Collaboration Agreement (Details) € in Millions, £ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2023 EUR (€)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2023 EUR (€)	Dec. 31, 2023 GBP (£)
Significant agreements.
Deferred revenue	$ 135,194,000		$ 61,873,000	$ 71,340,000
Oxurion
Significant agreements.
Revenue recognized	0		$ 0	$ 0
Deferred revenue	$ 0
Oxurion \| Development milestone
Significant agreements.
Potential milestone payments \| €					€ 8.3
Revenue under contracts with customer from milestone payment \| €		€ 3.8
Oxurion \| Regulatory milestone
Significant agreements.
Potential milestone payments \| £						£ 16.5
Oxurion \| Granting first regulatory approval or first indication
Significant agreements.
Potential milestone payments \| £						£ 5.0