Quarterly report pursuant to Section 13 or 15(d)

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

v3.21.2
License, Clinical Trial and Sponsored Research Agreements (Other - Sponsored Research and Clinical Trial Agreements) (Narrative) (Details) - USD ($)
$ in Thousands
1 Months Ended 3 Months Ended 9 Months Ended
Jul. 01, 2020
Jul. 03, 2017
Jun. 30, 2021
Nov. 30, 2020
Sep. 30, 2021
Sep. 30, 2020
Sep. 30, 2021
Sep. 30, 2020
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]                
Research and development expense         $ 14,083 $ 7,987 $ 36,603 $ 27,131
Sponsored Research and Clinical Trial Agreements [Member]                
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]                
Research and development expense         1,756 734 4,858 4,900
Fred Hutchinson Cancer Research Center [Member] | Sponsored Research and Clinical Trial Agreements [Member] | CD20 (MB-106) [Member]                
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]                
Milestones payable   $ 5,300            
Additional milestone payments       $ 800        
Research and development expense         492 418 1,490 1,134
St. Jude Children's Research Hospital [Member] | Sponsored Research and Clinical Trial Agreements [Member] | ST. Jude - XSCID [Member]                
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]                
Upfront fees paid $ 1,100              
Research and development expense         330 107 610 1,665
Mayo Clinic [Member] | Sponsored Research and Clinical Trial Agreements [Member]                
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]                
Research and development expense         231 $ 0 464 $ 0
Mayo Clinic [Member] | Sponsored Research and Clinical Trial Agreements [Member] | Car T Technology [Member]                
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]                
Milestones payable     $ 2,100          
Research and development expense         $ 200   $ 500  
Agreement term     2 years