Annual report pursuant to Section 13 and 15(d)

Commitment and Contingencies - Additional Information (Details)

v3.20.1
Commitment and Contingencies - Additional Information (Details) - USD ($)
$ in Millions
1 Months Ended 12 Months Ended
May 31, 2016
Mar. 31, 2015
Dec. 31, 2014
Aug. 31, 2012
May 31, 2011
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Other Commitments [Line Items]                
Rent expense           $ 3.6 $ 3.6 $ 2.2
Second Facility In South San Francisco                
Other Commitments [Line Items]                
Lessee operating lease fixed rental payment period 2021-11              
Option to extend lease term 2026-11              
South San Francisco Facility                
Other Commitments [Line Items]                
Lessee operating lease fixed rental payment period 2021-11              
Option to extend lease term 2026-11              
San Carlos California Facility | California                
Other Commitments [Line Items]                
Lessee operating lease fixed rental payment period       2016-07        
Option to extend lease term     2027-07          
Initial operating lease agreement period         2011-05      
Lease, extended lease term     2021-07          
Description of options to extend the lease term           two three-year options to extend the lease term    
Second Facility in San Carlos | California                
Other Commitments [Line Items]                
Lessee operating lease fixed rental payment period   2021-06            
Option to extend lease term   2027-06            
Initial operating lease agreement period   2015-03            
Description of options to extend the lease term           two three-year options to extend the lease term