Quarterly report pursuant to Section 13 or 15(d)

Revenue - Narrative (Details)

v3.20.1
Revenue - Narrative (Details)
€ in Millions
 1 Months Ended 3 Months Ended
Feb. 08, 2018
USD ($)
Feb. 08, 2018
USD ($)
swap_option
Feb. 08, 2018
USD ($)
Feb. 08, 2018
USD ($)
research_program
Feb. 08, 2018
USD ($)
performance_obligation
Feb. 08, 2018
USD ($)
license
May 02, 2017
USD ($)
performance_obligation
Jan. 04, 2017
EUR (€)
bispecific_therapeutic_program
performance_obligation
extension_option
product
license
Jan. 04, 2017
USD ($)
bispecific_therapeutic_program
performance_obligation
extension_option
product
license
Mar. 31, 2020
USD ($)
Feb. 28, 2019
EUR (€)
Feb. 28, 2019
USD ($)
Dec. 31, 2018
EUR (€)
Dec. 31, 2018
USD ($)
Mar. 31, 2020
USD ($)
performance_obligation
Dec. 31, 2019
USD ($)
Jan. 01, 2019
USD ($)
Disaggregation of Revenue [Line Items]                                  
Revenue recognized from contract with customer                             $ 10,000,000.0    
Deferred revenues, current portion                   $ 10,044,000         10,044,000 $ 11,256,000  
Deferred revenue, net of current portion                   38,560,000         38,560,000 $ 47,258,000  
Additions to deferred revenue                             1,600,000    
Seattle Genetics                                  
Disaggregation of Revenue [Line Items]                                  
Deferred revenues, current portion                   3,500,000         3,500,000    
Deferred revenue, net of current portion                   16,200,000         16,200,000    
AstraZeneca                                  
Disaggregation of Revenue [Line Items]                                  
Deferred revenues, current portion                   1,000,000.0         1,000,000.0    
Deferred revenue, net of current portion                   17,000,000.0         17,000,000.0    
Research collaboration agreement term             5 years                    
Les Laboratoires Servier and Institut de Recherches Internationales Servier                                  
Disaggregation of Revenue [Line Items]                                  
Revenue recognized from contract with customer                   7,100,000              
Number of performance obligations | performance_obligation               10 10                
Deferred revenues, current portion                   5,500,000         5,500,000    
Deferred revenue, net of current portion                   5,400,000         5,400,000    
Capitalized Contract Cost, Net                   100,000         100,000    
Amortization of capitalized contract costs                             $ 100,000    
Les Laboratoires Servier and Institut de Recherches Internationales Servier | Research and Development Services                                  
Disaggregation of Revenue [Line Items]                                  
Research collaboration agreement term               3 years 3 years                
License and Collaboration Agreement | Seattle Genetics                                  
Disaggregation of Revenue [Line Items]                                  
Period after effective date agreements may be terminated 12 months                                
Contract termination advance notice period 90 days                                
Agreement termination advance notice period if marketing approval obtained 180 days                                
Agreement termination notice period upon material breach by the Company 90 days                                
Contract termination due to material breach, additional notice period if the breach is not susceptible 90 days                                
Number of licenses (in licenses) | license           3                      
Number of swap options (in swap options) | swap_option   2                              
Number of performance obligations       3 6                   3    
License and Collaboration Agreement | AstraZeneca                                  
Disaggregation of Revenue [Line Items]                                  
Period after effective date agreements may be terminated             12 months                    
Contract termination advance notice period             90 days                    
Agreement termination advance notice period if marketing approval obtained             180 days                    
Agreement termination notice period upon material breach by the Company             180 days                    
Contract termination due to material breach, additional notice period if the breach is not susceptible             180 days                    
Number of performance obligations | performance_obligation             16                    
Agreement termination notice period upon breach of payment obligations by the Company             30 days                    
License and Collaboration Agreement | Les Laboratoires Servier and Institut de Recherches Internationales Servier                                  
Disaggregation of Revenue [Line Items]                                  
Number of licenses (in licenses) | license               5 5                
Number of performance obligations | performance_obligation               4 4                
Number of research programs | bispecific_therapeutic_program               5 5                
Strategic Partnerships and Other License Agreements | Les Laboratoires Servier and Institut de Recherches Internationales Servier                                  
Disaggregation of Revenue [Line Items]                                  
Revenue recognized from contract with customer                     € 1.5 $ 1,700,000 € 0.5 $ 600,000      
Period after effective date agreements may be terminated               12 months 12 months                
Contract termination advance notice period               180 days 180 days                
Number of collaboration products | product               4 4                
Upfront Payment | Seattle Genetics                                  
Disaggregation of Revenue [Line Items]                                  
Research and development services     $ 4,900,000                            
Deferred revenue $ 1,200,000,000 $ 1,200,000,000 1,200,000,000 $ 1,200,000,000 $ 1,200,000,000 $ 1,200,000,000                      
Upfront Payment | Seattle Genetics | License fees                                  
Disaggregation of Revenue [Line Items]                                  
Revenue     $ 30,000,000.0                            
Upfront Payment | AstraZeneca                                  
Disaggregation of Revenue [Line Items]                                  
Allocable arrangement consideration             $ 45,000,000.0                    
Upfront Payment | Strategic Partnerships and Other License Agreements | Les Laboratoires Servier and Institut de Recherches Internationales Servier | License fees                                  
Disaggregation of Revenue [Line Items]                                  
Revenue               € 30.0 $ 32,000,000.0                
Additional Other Research Services | AstraZeneca                                  
Disaggregation of Revenue [Line Items]                                  
Allocable arrangement consideration             4,700,000                    
Estimated Development and Manufacturing Services | Upfront Payment | AstraZeneca                                  
Disaggregation of Revenue [Line Items]                                  
Allocable arrangement consideration             14,200,000                    
Milestone Payments | Upfront Payment | AstraZeneca                                  
Disaggregation of Revenue [Line Items]                                  
Allocable arrangement consideration             12,500,000                    
Estimated Phase 2a Services | Upfront Payment | AstraZeneca                                  
Disaggregation of Revenue [Line Items]                                  
Allocable arrangement consideration             $ 4,700,000                    
Extension Term | Les Laboratoires Servier and Institut de Recherches Internationales Servier | Research and Development Services                                  
Disaggregation of Revenue [Line Items]                                  
Research collaboration agreement term               1 year 1 year                
Number of agreement extension options | extension_option               2 2                
Minimum | Strategic Partnerships and Other License Agreements | Les Laboratoires Servier and Institut de Recherches Internationales Servier                                  
Disaggregation of Revenue [Line Items]                                  
Agreement termination notice period upon material breach by the Company               90 days 90 days                
Maximum | Strategic Partnerships and Other License Agreements | Les Laboratoires Servier and Institut de Recherches Internationales Servier                                  
Disaggregation of Revenue [Line Items]                                  
Agreement termination notice period upon material breach by the Company               120 days 120 days                
Accounting Standards Update 2014-09 | AstraZeneca                                  
Disaggregation of Revenue [Line Items]                                  
Capitalized Contract Cost, Net                   $ 600,000         $ 600,000   $ 1,600,000
Capitalized contract cost in accordance with ASC 340                                 1,100,000
Amortization of capitalized contract costs                             $ 0    
Accounting Standards Update 2014-09 | Les Laboratoires Servier and Institut de Recherches Internationales Servier                                  
Disaggregation of Revenue [Line Items]                                  
Capitalized Contract Cost, Net                                 $ 500,000