Income taxes - Components of Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Deferred tax assets:
Net operating losses	$ 122,010	$ 126,798
R&D capitalization	67,837	67,107
Tax credit carryforwards	33,823	28,409
Deferred revenue	26,779	3,688
Stock-based compensation	7,156	6,899
Capitalized licenses	2,412	2,725
Accrued expenses	2,191	3,142
Lease liabilities	1,407	2,274
Depreciation	353	353
Other	130	156
Total gross deferred tax assets	264,098	241,551
Valuation allowance	(262,845)	(239,468)
Net deferred tax assets less valuation allowance	1,253	2,083
Deferred tax liabilities
Right-of-use assets	(1,253)	(2,083)
Total gross deferred tax liabilities	(1,253)	(2,083)
Net deferred taxes	$ 0	$ 0