Share-Based Payments - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense for options	$ 32,100
Weighted-average period to recognize compensation expense (in years)	1 year 9 months 18 days
Performance Stock Unit, Probable of Meeting Vesting Criteria
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock based compensation expense	$ 2,000
Weighted-average period to recognize compensation expense (in years)	7 months 6 days
Market-Based Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense for options	$ 1,100
Weighted-average period to recognize compensation expense (in years)	1 year
2007 Plan and 2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance (in shares)	9,392,668
2013 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance (in shares)	2,248,177
Unrecognized compensation expense for options	$ 102,300
Weighted-average period to recognize compensation expense (in years)	2 years 8 months 12 days
2013 Stock Incentive Plan \| Performance Stock Unit, Not Probable of Meeting Vesting Criteria
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock based compensation expense	$ 7,200
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance (in shares)	82,555
Shares issued under 2013 ESPP (in shares)	77,981	53,255
Opportunity to purchase of common stock (in shares)	327,272

Aggregate number of common shares reserved for future issuance.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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