Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2018

Equity [Abstract]

Schedule of reserve shares of common stock for issuance

The Company has reserved shares of common stock for issuance as follows (in thousands):

	December 31,
	2018	2017
Stock plans
Shares available for grant
2015 Equity Incentive Plan	11,986	8,857
2015 Employee Stock Purchase Plan	5,202	3,970
Options outstanding	13,590	16,268
Restricted stock units outstanding	4,182	5,330
Total	34,960	34,425