Share-Based Payments - Additional Information (Details) - USD ($)	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense for options	$ 51,100,000
Weighted-average period to recognize compensation expense (in years)	2 years 1 month 6 days
Market-Based Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense for options	$ 200,000
Weighted-average period to recognize compensation expense (in years)	2 months 12 days
2007 Plan and 2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance (in shares)	10,749,789
2013 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance (in shares)	2,688,890
Unrecognized compensation expense for options	$ 94,200,000
Weighted-average period to recognize compensation expense (in years)	2 years 6 months
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 compensation expense for options	$ 0
Unrecognized stock based compensation expense	$ 6,900,000
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance (in shares)	528,952
Shares issued under 2013 ESPP (in shares)	62,694	32,410
Opportunity to purchase of common stock (in shares)	836,363

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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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for option under share-based payment arrangement.

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The highest quantity of shares an employee can purchase under the plan per period.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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