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Stockholders' Equity - Additional Information (Details) - USD ($)	1 Months Ended			12 Months Ended
	Aug. 31, 2018	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issued under ESPP (in shares)				201,581	253,301
Weighted average purchase price of shares purchased (in dollars per share)				$ 25.55	$ 15.77
Exercises in period, intrinsic value				$ 90,800,000	$ 57,200,000	$ 16,800,000
Capitalized share-based compensation expense				$ 0	0	$ 0
Restricted Stock Units (RSUs) | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards				3 years
Restricted Stock Units (RSUs) | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards				4 years
Performance-based restricted stock units | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards				2 years
Performance-based restricted stock units | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards				3 years
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from issuance of shares under ESPP				$ 5,100,000	$ 4,000,000.0
RSUs and PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance based restricted stock unit award granted to executive officers (in shares)				2,910,400
Performance based restricted stock unit award granted weighted average grant date fair value (in dollars per share)				$ 37.56	$ 21.67	$ 9.10
Total fair value of awards vested				$ 222,300,000	$ 120,900,000	$ 49,400,000
Unrecognized compensation costs related to restricted stock units				$ 91,200,000
Weighted average vesting period for recognition of compensation expense				1 year 7 months 6 days
2013 Plan | Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards				3 years
2019 Performance Period | Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance based restricted stock unit award granted weighted average grant date fair value (in dollars per share)				$ 40.42
March 2019 PSU Grants | Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance based restricted stock unit award granted to executive officers (in shares)				436,042
March 2018 PSU Grants | Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards		3 years
Performance based restricted stock unit award granted to executive officers (in shares)					845,934
Performance based restricted stock unit award granted weighted average grant date fair value (in dollars per share)					$ 19.70
2017 Performance Period | Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards			3 years
Performance based restricted stock unit award granted to executive officers (in shares)						1,822,284
Performance based restricted stock unit award granted weighted average grant date fair value (in dollars per share)						$ 8.91
2018 Performance Period | Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock awards	3 years
Performance based restricted stock unit award granted to executive officers (in shares)					45,756
Performance based restricted stock unit award granted weighted average grant date fair value (in dollars per share)					$ 28.74
Common Stock Warrant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock warrants remaining(in shares)					0
Weighted average exercise price (in dollars per share)					$ 12.00	$ 12.00
Common stock warrants exercised					100,000	100,000

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