Quarterly report [Sections 13 or 15(d)]

Basis of Presentation and Significant Accounting Policies - Cash, Cash Equivalents and Restricted Cash (Details)

v3.26.1
Basis of Presentation and Significant Accounting Policies - Cash, Cash Equivalents and Restricted Cash (Details) - USD ($)
$ in Thousands
 3 Months Ended
Jul. 01, 2027
Dec. 15, 2025
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Dec. 31, 2024
Cash, Cash Equivalents and Restricted Cash            
Unrestricted cash     $ 10,260   $ 34,768  
Unrestricted cash equivalents     75,340   48,140  
Total unrestricted cash and cash equivalents     85,600   82,908  
Short-term restricted cash     8,862   5,441  
Long-term restricted cash     44,281   45,361  
Total restricted cash     53,143   50,802  
Total unrestricted and restricted cash and cash equivalents     138,743 $ 95,027 133,710 $ 106,416
Cash and Cash Equivalents            
Allowance for credit losses on investments in debt securities     0      
Redemption or sale of available-for-sale debt securities     20,300 20,500    
Gains from redemption or sale of available-for-sale debt securities     100 $ 200    
Available for sale securities, Amortized Cost Basis     25,386   6,277  
Available for sale securities, Unrealized Gains     119   53  
Available for sale securities, Estimated Fair Value     25,505   6,330  
Restricted Cash            
Restricted cash released to unrestricted cash   $ 3,800        
U.S. treasury bills            
Cash and Cash Equivalents            
Available for sale securities, Amortized Cost Basis     25,386   6,277  
Available for sale securities, Unrealized Gains     119   53  
Available for sale securities, Estimated Fair Value     25,505   6,330  
Cash reserve accounts            
Cash, Cash Equivalents and Restricted Cash            
Total restricted cash   6,300        
Cash reserve account, Interest and administrative fees            
Cash, Cash Equivalents and Restricted Cash            
Total restricted cash   5,800        
Cash reserve account, Interest and administrative fees | Forecast            
Restricted Cash            
Additional amount of cash required to fund reserve account $ 800          
Cash reserve account, Operating expenses            
Cash, Cash Equivalents and Restricted Cash            
Total restricted cash   $ 500        
Restricted cash held for Blue Owl Loan            
Cash, Cash Equivalents and Restricted Cash            
Short-term restricted cash     1,410   160  
Long-term restricted cash     680   2,011  
Restricted cash held for Boston Lease security deposit            
Cash, Cash Equivalents and Restricted Cash            
Long-term restricted cash     1,631   1,631  
Restricted cash held for Boston Lease payments            
Cash, Cash Equivalents and Restricted Cash            
Short-term restricted cash     5,320   5,281  
Long-term restricted cash     34,866   35,386  
Restricted cash held for Binney Lease security deposit            
Cash, Cash Equivalents and Restricted Cash            
Short-term restricted cash     2,051      
Restricted cash held for Generation Bio post-closing expenses            
Cash, Cash Equivalents and Restricted Cash            
Short-term restricted cash     81      
Long-term restricted cash     360      
Restricted cash held for the acquisition of Mural            
Cash, Cash Equivalents and Restricted Cash            
Long-term restricted cash     44,281   45,361  
Restricted cash held for LAVA CVR payments            
Cash, Cash Equivalents and Restricted Cash            
Long-term restricted cash     $ 6,744   $ 6,333