Convertible Preferred Stock and Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2014

Stockholders' Equity

Schedule of reserve for unissued shares of common stock

	Number of Shares
Outstanding stock options	25,589,876
Outstanding restricted stock units	827,997
Outstanding common stock warrants	3,925,643
Additional shares available for grant under equity plan	1,123,732
Total	31,467,248