Equity Incentive Plans - Additional Information (Details) $ in Millions	9 Months Ended
Sep. 30, 2018 USD ($) shares
Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost \| $	$ 8.1
Weighted-average remaining expected term	1 year 9 months 18 days
RSU
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average remaining expected term	3 years 1 month 6 days
Unrecognized compensation cost \| $	$ 52.0
2016 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future issuance	5,741,611
Automatically increase percentage of shares of all classes of company's common stock outstanding	5.00%
2016 Equity Incentive Plan \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Automatically increase of shares reserved for issuance	5,500,000
2016 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Automatically increase percentage of shares of all classes of company's common stock outstanding	1.00%
2016 Employee Stock Purchase Plan \| Class A Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future issuance	1,117,643
Automatically increase of shares reserved for issuance	1,600,000
Purchase price of common stock, percent	85.00%
Number of shares purchased	125,121

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