Employee Defined Contribution Plans (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Mainland China Government Plan
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan expense	$ 25.8	$ 23.6	$ 17.6
401(k) Plan
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan expense	$ 1.0	$ 0.5	$ 0.0
Employer matching contribution percentage	100.00%	50.00%	50.00%
Percentage of employee contribution that the employer matches	5.00%	5.00%	5.00%
Mandatory Provident Fund
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan expense	$ 0.2	$ 0.2	$ 0.0
Maximum \| 401(k) Plan
Defined Contribution Plan Disclosure [Line Items]
Percentage of employees eligible compensation the employer matches	5.00%	5.00%	5.00%

Amount of cost for defined contribution plan.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480794/715-70-50-1

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+ References

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