v3.6.0.2
STOCKHOLDERS' EQUITY - Common Stock Reserved for Future Issuance (Details) - shares
Dec. 31, 2016
Dec. 31, 2015
Class of Stock [Line Items]    
Total reserved shares of common stock for future issuance 17,277,802  
Employee Stock Options and Restricted Stock Units    
Class of Stock [Line Items]    
Options and Restricted Stock Units issued and outstanding 10,585,444  
2014 Equity Incentive Plan    
Class of Stock [Line Items]    
Shares reserved for issuance under share-based compensation plan 5,116,753 5,017,525
Employee Stock Purchase Plan | ESPP    
Class of Stock [Line Items]    
Shares reserved for issuance under share-based compensation plan 1,575,605