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Stock-Based Compensation - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant	4,400,000
Common stock, par value (in dollars per share)	$ 0.0005	$ 0.0005
Total share-based compensation cost not yet recognized	$ 84,600,000
Remaining weighted average service period	2 years 4 months 24 days
Proceeds from employee stock purchase plan	$ 18,085,000	$ 17,629,000	$ 14,689,000
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee stock purchase plan, stock purchases as a percentage of employee compensation, maximum	10.00%
Maximum share value authorized for purchase under employee stock purchase plan	$ 23,750
Exercisable price percentage of closing price of another class of stock	95.00%
Maximum number of shares that may be purchased by eligible participants	400,000
Proceeds from employee stock purchase plan	$ 18,100,000	$ 17,600,000	$ 14,700,000
Stock appreciation rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining weighted average service period	6 years 1 month 6 days
Award vesting period	4 years
Award expiry period from date of grant	7 years
Total compensation cost not yet recognized, period for recognition	4 years
Restricted stock units \| Service-based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Restricted stock units \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
CSEs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Base fee percentage	50.00%