Income taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Taxes [Line Items]
Swiss federal statutory tax rate	8.50%	8.50%	8.50%
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 1,261,855	$ 13,427
Effective corporate tax	11.90%
Non-U.S NOLs	$ 23,936
NOLs carry forwards indefinitely	2,342
Uncertain tax positions, interest and penalties recognized	0	$ 2	$ 2
Swiss Federal Tax Administration (FTA)
Income Taxes [Line Items]
Federal NOLs	1,061,639
State and Local Jurisdiction | Swiss Federal Tax Administration (FTA)
Income Taxes [Line Items]
Federal NOLs	$ 1,033,880