Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2017

Equity [Abstract]

Shares of Common Stock Reserved for Future Issuance

As of December 31, 2017 and 2016, the Company had shares of common stock reserved for future issuance as follows:

December 31,	2017	2016
Options and unvested RSUs outstanding	47,538,097	62,082,821
Available for future stock option and RSU grants	49,277,465	28,449,336
Available for ESPP	8,695,999	5,408,441
Total reserved for future issuance	105,511,561	95,940,598