Condensed Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Jun. 30, 2019	Dec. 31, 2018
Temporary equity, shares authorized	115,185,867	105,003,754
Temporary equity, shares issued	114,960,357	104,778,246
Temporary equity, shares outstanding	114,960,357	104,778,246
Common stock, par value	$ 0.00001	$ 0.00001
Common stock, shares authorized	155,649,887	145,467,774
Common stock, shares issued	9,701,266	8,593,077
Common stock, shares, outstanding	9,701,266	8,593,077
Redeemable Convertible Preferred Stock
Temporary equity, par value	$ 0.00001	$ 0.00001
Temporary equity, shares authorized	37,403,946	31,053,601
Temporary equity, shares issued	37,403,946	31,053,601
Temporary equity, shares outstanding	37,403,946	31,053,601
Convertible Preferred Stock
Temporary equity, par value	$ 0.00001	$ 0.00001
Temporary equity, shares authorized	77,781,921	73,950,153
Temporary equity, shares issued	77,556,411	73,724,645
Temporary equity, shares outstanding	77,556,411	73,724,645

Face amount or stated value per share of common stock.

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