Convertible Preferred Stock and Stockholders'Equity (Deficit) - Summary of Early Exercise of Stock Options (Details) - 2014 Plan	6 Months Ended
Jun. 30, 2019 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Balance as of December 31, 2018	709,123
Shares vested	(156,490)
Balance as of June 30, 2019	552,633

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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