Quarterly report pursuant to Section 13 or 15(d)

Commitments and Contingencies - Leases (Details)

v3.20.2
Commitments and Contingencies - Leases (Details)
$ in Thousands
1 Months Ended
Oct. 11, 2018
ft²
$ / ft²
Nov. 30, 2017
USD ($)
ft²
Oct. 31, 2017
USD ($)
Jun. 30, 2020
ft²
Chesterbrook, Pennsylvania        
Leases        
Number of square feet of space leased on the first floor       8,231
Number of square feet of space leased on the second floor       40,565
Chesterbrook, Pennsylvania | Sublease Agreements | Vanguard Group, Inc        
Leases        
Number of square feet of space being subleased on second floor 40,565      
Initial term of sublease 37 months      
Term of optional sublease extension 3 years      
Amount per square foot less for rent during months 2 to 13 | $ / ft² 0.50      
Amount per square foot for rent after month 14 | $ / ft² 1.00      
King of Prussia, Pennsylvania        
Leases        
Termination fees for cancellation of lease | $   $ 150    
Area of office and laboratory space where lease terminated   16,714    
Exton, Pennsylvania | Maximum        
Leases        
Termination fees for cancellation of lease | $     $ 100