Equity Award Plans - Series E-1 Preferred Stock Options (Details) - shares		6 Months Ended
May 08, 2018	Jun. 30, 2018
Common Stock
Additional disclosures
Series E-1 options converted to common stock options upon IPO (in shares)	837,835	837,835
Redeemable convertible preferred stock, Series E-1
Additional disclosures
Converted to common stock options upon IPO (in shares)	837,835

Share-based Compensation Arrangement by Share-based Payment Award, Options, Converted to Common Stock Options in Period from Redeemable Convertible Preferred Stock

No definition available.

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