Commitments and contingencies - Leases, Maturities of operating leases (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2023	Dec. 31, 2022
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
2023	$ 2,841
2024	5,767
2025	5,855
2026	3,347
2027	821
Present value adjustment	(2,070)
Total lease liabilities	16,561
Less: current lease liabilities	$ (4,680)	$ (3,125)
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued Liabilities and Other Liabilities, Current	Accrued Liabilities and Other Liabilities, Current
Long term lease liabilities	$ 11,881	$ 10,885
Maximum days allowed for cancellation of contracts prior written notice	90 days
Agreement With Third Party
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone payments	$ 92,400
Future milestone payment payable	1,300
Agreement With CRUK
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Future milestone payment receivable	$ 111,200

Amount of future milestone payment payable upon the achievement of development, regulatory and commercial milestones,

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- Definition

Amount of future milestone payment receivable upon the achievement of development, regulatory and commercial milestones,

+ References

No definition available.

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- Definition

Maximum days allowed for cancellation of contracts prior written notice, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount payable to for the achievement of various milestones.

+ References

No definition available.

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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.

+ 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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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-6

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease having initial or remaining lease term in excess of one year to be paid in remainder of current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-6

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- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

+ References

+ Details

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479041/842-20-45-1

+ Details

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

+ References

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- Definition

Indicates line item in statement of financial position that includes current operating lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479041/842-20-45-2

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

+ References

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