Employee Benefit Plans - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution, percent of match			8.30%
Defined benefit plan, accumulated benefit obligation	$ 18.7		$ 18.7		$ 20.1
Periodic benefit costs	0.1	$ 0.1	0.2	$ 0.2
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, insurance contract amount	3.3		3.3		$ 3.5
US
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan expense	0.1	0.0	0.4	0.0
Korea
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan expense	$ 0.3	$ 0.4	$ 0.9	$ 1.0