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Share-Based Compensation (Details) - USD ($) $ in Thousands		9 Months Ended
Share-Based Compensation (Details) - USD ($) $ in Thousands	Jan. 01, 2026	Sep. 30, 2026	Dec. 31, 2025
Options
Share-Based Compensation
Shares outstanding (in shares)		8,737,521	9,420,208
Number of options granted		1,308,888
RSUs, revenue PSUs, TSR PSUs, and share options
Share-Based Compensation
Total unrecognized compensation cost		$ 145,286
Expenses expected to be recognized over a weighted average remaining period		2 years 6 months
Development PSUs and PSOs
Share-Based Compensation
Total unrecognized compensation cost		$ 10,147
Unvested PSUs
Share-Based Compensation
Service period		3 years
2018 Plan
Share-Based Compensation
Number of ordinary shares available for future grant		7,226,845
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)		77,247
2018 ESPP \| Class A ordinary shares
Share-Based Compensation
Number of ordinary shares available for future grant		739,089
2018 ESPP \| Class A ordinary shares \| Maximum
Share-Based Compensation
Additional shares authorized	110,000