Annual report pursuant to Section 13 and 15(d)

License, Clinical Trial and Sponsored Research Agreements (Other - Licenses) (Narrative) (Details)

v3.21.1
License, Clinical Trial and Sponsored Research Agreements (Other - Licenses) (Narrative) (Details)
€ in Millions
 1 Months Ended 12 Months Ended
Aug. 23, 2019
USD ($)
item
Aug. 02, 2018
USD ($)
item
Nov. 20, 2017
USD ($)
Jul. 03, 2017
USD ($)
Oct. 31, 2020
USD ($)
item
Oct. 31, 2020
EUR (€)
item
Feb. 28, 2019
USD ($)
Dec. 31, 2020
USD ($)
item
Dec. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]                    
Research and development for licenses acquired               $ 10,064,000 $ 6,273,000  
License Agreements [Member]                    
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]                    
Research and development for licenses acquired               10,064,000 6,273,000  
CSL Behring (Calimmune) [Member] | License Agreements [Member]                    
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]                    
Number of milestones | item 3                  
Upfront fees paid $ 200,000                  
Milestones payable $ 1,200,000                  
Research and development for licenses acquired               170,000 200,000  
Nationwide Childrens Hospital [Member] | License Agreements [Member] | Nationwide - C134 [Member]                    
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]                    
Upfront fees paid             $ 200,000      
Milestones payable             $ 152,800,000      
Research and development for licenses acquired               0 200,000  
University of California [Member] | License Agreements [Member]                    
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]                    
Research and development for licenses acquired               0 300,000  
Fred Hutchinson Cancer Research Center [Member] | License Agreements [Member] | CD20 Product or Process [Member]                    
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]                    
Upfront fees paid       $ 300,000            
Annual maintenance fee payable       50,000            
Additional milestone payments       $ 39,100,000            
Research and development for licenses acquired               300,000 0  
St. Jude Children's Research Hospital [Member] | License Agreements [Member] | ST. Jude - XSCID [Member]                    
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]                    
Number of milestones | item   5                
Upfront fees paid   $ 1,000,000.0                
Milestones payable   13,500,000                
Annual maintenance fee payable   $ 100,000                
Research and development for licenses acquired               0 0  
SIRION Biotech GmbH - LentiBOOST [Member] | License Agreements [Member]                    
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]                    
Number of milestones | item         3 3        
Upfront fees paid         $ 100,000 € 0.1        
Milestones payable         5,600,000 4.7        
Additional milestone payments         $ 4,100,000 € 3.5        
Research and development for licenses acquired               $ 117,000 0  
Number of milestones payments | item         5 5        
Harvard University [Member] | License Agreements [Member] | CRISPR [Member]                    
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]                    
Number of milestones | item               7    
Upfront fees paid     $ 300,000              
Annual maintenance fee payable               $ 100,000 50,000 $ 25,000
Additional milestone payments               16,700,000    
Research and development for licenses acquired               $ 0 $ 0