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Stockholders' Equity - Additional Information (Details) - USD ($)	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued in connection with employee stock purchase plan (in shares)							49,972,000
Restricted stock granted, weighted average fair value (in USD per share)							$ 97.33
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 156,300,000						$ 156,300,000
Repurchases of common stock (in shares)	10,157						257,329
Repurchases of common stock	$ 2,384,000	$ 42,894,000	$ 1,954,000	$ 29,000	$ 395,000	$ 1,476,000
Stock Repurchase Program, Authorized Amount	$ 150,000,000.0						$ 150,000,000.0
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Repurchases of common stock (in shares)	14,000	252,000	25,000	1,000	7,000	24,000
Repurchases of common stock	$ 1,500,000						43,700,000
Additional paid-in capital
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Repurchases of common stock	2,384,000	$ 42,894,000	$ 1,954,000	$ 29,000	$ 395,000	$ 1,476,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 35,800,000						$ 35,800,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected weighted-average period of recognition for unrecognized compensation expense							1 year 9 months 18 days
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock granted, weighted average fair value (in USD per share)							$ 97.33	$ 59.45