Annual report pursuant to Section 13 and 15(d)

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

v3.23.1
License, Clinical Trial and Sponsored Research Agreements (Other - Sponsored Research and Clinical Trial Agreements) (Narrative) (Details) - USD ($)
$ in Thousands
1 Months Ended 12 Months Ended
Sep. 08, 2021
Apr. 01, 2021
Jul. 03, 2017
Oct. 31, 2022
Jan. 31, 2022
Jun. 30, 2021
Nov. 30, 2020
Jun. 30, 2020
Dec. 31, 2022
Dec. 31, 2021
License, Clinical Trial and Sponsored Research Agreements                    
Research and development expense                 $ 62,475 $ 49,864
Sponsored Research and Clinical Trial Agreements [Member]                    
License, Clinical Trial and Sponsored Research Agreements                    
Research and development expense                 6,989 6,591
Fred Hutchinson Cancer Center [Member] | Sponsored Research and Clinical Trial Agreements [Member] | CD20 (MB-106) [Member]                    
License, Clinical Trial and Sponsored Research Agreements                    
Milestones payable     $ 5,300              
Additional milestone payments         $ 2,200   $ 1,800      
Research and development expense                 1,987 1,979
Fred Hutchinson Cancer Center [Member] | Clinical Trial Agreements [Member] | CD20 (MB-106) [Member]                    
License, Clinical Trial and Sponsored Research Agreements                    
Research and development expense                 2,000 2,000
Total reimbursement payments made                 7,200  
St. Jude Children's Research Hospital [Member] | Sponsored Research and Clinical Trial Agreements [Member] | ST. Jude - XSCID [Member]                    
License, Clinical Trial and Sponsored Research Agreements                    
Research and development expense                 508 865
St. Jude Children's Research Hospital [Member] | Data Transfer Agreement [Member] | ST. Jude - XSCID [Member]                    
License, Clinical Trial and Sponsored Research Agreements                    
Upfront fees paid               $ 1,100    
Research and development expense                 500 900
Total reimbursement payments made                 3,000  
Mayo Clinic [Member]                    
License, Clinical Trial and Sponsored Research Agreements                    
Upfront fees paid   $ 800                
Mayo Clinic [Member] | Sponsored Research and Clinical Trial Agreements [Member]                    
License, Clinical Trial and Sponsored Research Agreements                    
Milestones payable           $ 2,100        
Additional milestone payments       $ 100            
Research and development expense                 968 695
Agreement term           2 years        
Leiden University Medical Centre [Member] | Sponsored Research and Clinical Trial Agreements [Member] | RAG1 SCID (MB-110) [Member]                    
License, Clinical Trial and Sponsored Research Agreements                    
Milestones payable $ 500                  
Research and development expense                 $ 505 $ 170
Agreement term 5 years