Commitments and Contingencies (Details)
1 Months Ended 12 Months Ended 20 Months Ended
Jan. 31, 2015
ft²
Dec. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Aug. 31, 2016
ft²
Facility Lease        
Landlord Provided Free Rent And Lease Incentives   $ 1,900,000    
Rent expense   584,000 $ 347,000  
Operating lease obligations        
Total   4,745,000    
Less than 1 Year   1,112,000    
2-3 years   2,321,000    
4-5 years   1,312,000    
Contractual obligations        
Total   4,745,000    
Less than 1 Year   1,112,000    
2-3 years   2,321,000    
4-5 years   $ 1,312,000    
Facilities lease | Office and laboratory space in Burlingame, California        
Facility Lease        
Area of leased facility | ft² 8,138      
Additional area of lease | ft²       28,633
Lease term 1 year      
Lease agreement, right to extend the term   3 years