v3.19.3.a.u2
Stockholders' Equity (Details) - USD ($)
$ in Thousands
 12 Months Ended
May 22, 2019
May 22, 2018
Sep. 11, 2017
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Stockholders' Equity            
Proceeds from issuance of common stock, net of offering costs   $ 330,900 $ 189,500 $ 0 $ 330,901 $ 189,463
Authorized shares of capital stock (in shares)       205,000,000    
Authorized shares of common stock (in shares)       200,000,000 200,000,000  
Authorized shares of preferred stock (in shares)       5,000,000 5,000,000  
Shares of common stock reserved for future issuance            
Outstanding stock options (in shares)       4,373,895    
Outstanding restricted stock units (in shares)       3,694,915    
Available for future issuance under Amended and Restated 2014 Equity Incentive Plan (in shares)       5,296,333    
Available for future issuance under employee stock purchase plan (in shares)       812,964    
Total shares of common stock reserved for future issuance (in shares)       14,178,107    
Common Stock            
Stockholders' Equity            
Issuance of common stock award (in shares) 4,608,101 3,833,334 4,047,500 4,608,101 3,833,334 4,047,500
Common Stock | Underwriters' over-allotment option            
Stockholders' Equity            
Issuance of common stock award (in shares)   500,000 547,500