Annual report pursuant to Section 13 and 15(d)

Organization and Summary of Significant Accounting Policies - Additional Information (Detail)

v3.20.1
Organization and Summary of Significant Accounting Policies - Additional Information (Detail)
 12 Months Ended
Dec. 31, 2019
USD ($)
Segment
Dec. 31, 2018
USD ($)
Jan. 01, 2019
USD ($)
Organization And Summary Of Significant Accounting Policies [Line Items]      
Reclassification from other current assets to grants revenue receivable $ 7,100,000 $ 4,329,000  
Impairment of long lived assets 22,100,000 0  
Right-of-use asset 9,959,000 $ 0 $ 4,180,000
Lease liabilities $ 13,365,000    
Lessee, operating leases remaining lease term. 7 years 2 months 12 days    
Lessee, finance leases remaining lease term. 9 months 18 days    
Reportable segment | Segment 1    
ASU 2016-02      
Organization And Summary Of Significant Accounting Policies [Line Items]      
Right-of-use asset     4,180,000
Lease liabilities     $ 4,700,000
Patents      
Organization And Summary Of Significant Accounting Policies [Line Items]      
Amortization expense $ 100,000    
Estimated expense, next twelve months 100,000    
Estimated expense, year two 100,000    
Estimated expense, year three 100,000    
Estimated expense, year four 100,000    
Estimated expense, year five $ 100,000    
Minimum      
Organization And Summary Of Significant Accounting Policies [Line Items]      
Lessee, operating leases remaining lease term. 3 years    
Lessee, finance leases remaining lease term. 1 year    
Lessee, operating leases renewal lease term 3 years    
Maximum      
Organization And Summary Of Significant Accounting Policies [Line Items]      
Lessee, operating leases remaining lease term. 9 years    
Lessee, finance leases remaining lease term. 2 years    
Lessee, operating leases renewal lease term 5 years    
Leasehold Improvements | Minimum      
Organization And Summary Of Significant Accounting Policies [Line Items]      
Property and equipment, estimated useful lives 5 years    
Leasehold Improvements | Maximum      
Organization And Summary Of Significant Accounting Policies [Line Items]      
Property and equipment, estimated useful lives 7 years    
Revenue | Takeda Pharmaceuticals Inc | Credit Risk      
Organization And Summary Of Significant Accounting Policies [Line Items]      
Percentage of total revenues 88.00% 53.00%  
Other Assets      
Organization And Summary Of Significant Accounting Policies [Line Items]      
Restricted cash $ 3,000,000    
Gross value of patents $ 1,300,000 $ 1,300,000