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Share-Based Compensation (Details) - USD ($) $ in Thousands		6 Months Ended
Share-Based Compensation (Details) - USD ($) $ in Thousands	Jan. 01, 2026	Jun. 30, 2026	Dec. 31, 2025
Options
Share-Based Compensation
Shares outstanding (in shares)		8,489,746	9,420,208
Number of options granted		704,571
RSUs, revenue PSUs, TSR PSUs, and share options
Share-Based Compensation
Total unrecognized compensation cost		$ 122,664
Expenses expected to be recognized over a weighted average remaining period		2 years 4 months 28 days
Development PSUs and PSOs
Share-Based Compensation
Total unrecognized compensation cost		$ 9,506
Unvested PSUs
Share-Based Compensation
Service period		3 years
2018 Plan
Share-Based Compensation
Number of ordinary shares available for future grant		7,845,077
2018 Plan \| Class A ordinary shares \| Maximum
Share-Based Compensation
Additional shares authorized	3,051,742
2015 Plan \| Class A ordinary shares
Share-Based Compensation
Shares outstanding (in shares)		77,296
2018 ESPP \| Class A ordinary shares
Share-Based Compensation
Number of ordinary shares available for future grant		765,514
2018 ESPP \| Class A ordinary shares \| Maximum
Share-Based Compensation
Additional shares authorized	110,000