Net Loss and Net Loss Per Share (Tables)

12 Months Ended

Dec. 31, 2019

Earnings Per Share [Abstract]

Schedule of Dilutive Securities Not Included in Diluted Per Share Calculations

Potentially dilutive securities that were not included in the diluted per share calculations because they would be anti-dilutive were as follows:

	Year Ended December 31,
	2019	2018	2017
Options issued and outstanding and ESPP shares issuable	11,921,434	9,789,594	6,835,313
Restricted shares subject to future vesting	882,636	503,243	2,293,788
Early exercised common stock subject to future vesting	—	135,424	369,796
Total	12,804,070	10,428,261	9,498,897