v3.26.1
Nature of Business (Details)
$ / shares in Units, $ in Thousands
 1 Months Ended 3 Months Ended 31 Months Ended 41 Months Ended
Feb. 19, 2026
USD ($)
$ / shares
shares
Jan. 05, 2026
USD ($)
installment
Jan. 13, 2025
shares
Aug. 18, 2023
$ / shares
shares
Aug. 16, 2023
$ / shares
shares
Oct. 08, 2021
USD ($)
Feb. 28, 2026
USD ($)
shares
Jan. 31, 2025
$ / shares
shares
Mar. 31, 2026
USD ($)
shares
Mar. 31, 2025
USD ($)
shares
Mar. 31, 2026
USD ($)
shares
Feb. 27, 2025
USD ($)
shares
Dec. 31, 2025
USD ($)
Jan. 31, 2025
£ / shares
shares
Feb. 29, 2024
Jun. 30, 2023
USD ($)
Conversion of Stock [Line Items]                                
Ordinary share conversion ratio (in shares)       1   1                    
Net income (loss)                 $ 91,202 $ (17,864)            
Accumulated deficit                 731,392   $ 731,392   $ 822,594      
Cash and cash equivalents                 $ 466,010 $ 260,110 $ 466,010   $ 149,608      
PIPE Warrants                                
Conversion of Stock [Line Items]                                
Sale of stock, shares issued in transaction (in shares) | shares                 0              
Issuance of ordinary shares to settle warrant exercised (in shares) | shares                 0 0 3,752,050          
Proceeds from the exercise of ADS warrants                     $ 37,300          
Proceeds from warrant exercises, fully exercised                 $ 122,400              
Loan Agreement                                
Conversion of Stock [Line Items]                                
Convertible notes, face amount                               $ 50,000
Loan Agreement, Term Loan One                                
Conversion of Stock [Line Items]                                
Convertible notes, face amount   $ 50,000                           $ 30,000
Amended Loan Agreement                                
Conversion of Stock [Line Items]                                
Convertible notes, face amount   $ 150,000                            
Number of tranches | installment   5                            
Repayments of debt   $ 31,100                            
At-The-Market Offering                                
Conversion of Stock [Line Items]                                
Sale of stock, shares issued in transaction (in shares) | shares                       5,491,836        
Consideration received on transaction                       $ 54,800        
Private Placement                                
Conversion of Stock [Line Items]                                
Ordinary share conversion ratio (in shares)         1                      
Sale of stock, shares issued in transaction (in shares) | shares       16,076,750 16,076,750                      
Sale of stock, price per share (in dollars per share) | $ / shares         $ 7.78                      
Warrant exercise price (in dollars per share) | $ / shares         $ 9.93                      
Private Placement | PIPE Warrants                                
Conversion of Stock [Line Items]                                
Warrant exercise price (in dollars per share) | $ / shares       $ 9.93                        
Term (in years)                             3 years  
Underwritten Offering                                
Conversion of Stock [Line Items]                                
Sale of stock, shares issued in transaction (in shares) | shares             15,160,619                  
Consideration received on transaction $ 140,500                              
Underwritten Offering | 2025 ADS Warrants                                
Conversion of Stock [Line Items]                                
Ordinary share conversion ratio (in shares)     1         1                
Sale of stock, shares issued in transaction (in shares) | shares     24,014,728         24,014,728                
Sale of stock, price per share (in dollars per share) | (per share)               $ 4.2750           £ 0.008    
Warrant exercise price (in dollars per share) | $ / shares               $ 5.7960                
Term (in years)               3 years           3 years    
Issuance of ordinary shares to settle warrant exercised (in shares) | shares             35,059,448                  
Proceeds from the exercise of ADS warrants             $ 203,200                  
Purchase of warrants (in shares) | shares             19,898,829 24,014,728           24,014,728    
Underwritten Offering | Pre-funded Warrants                                
Conversion of Stock [Line Items]                                
Sale of stock, price per share (in dollars per share) | $ / shares $ 7.9999             $ 4.2649                
Warrant exercise price (in dollars per share) | $ / shares               $ 0.0001                
Purchase of warrants (in shares) | shares 1,250,000           19,898,829 11,044,720           11,044,720    
Underwritten Offering | 2026 ADS Warrants                                
Conversion of Stock [Line Items]                                
Ordinary share conversion ratio (in shares) 1                              
Sale of stock, shares issued in transaction (in shares) | shares 17,500,000                              
Sale of stock, price per share (in dollars per share) | $ / shares $ 8.00                              
American Depositary Shares | Initial Public Offering                                
Conversion of Stock [Line Items]                                
Maximum amount of stock that may be sold           $ 150,000                    
Amount authorized           $ 150,000                    
American Depositary Shares | At-The-Market Offering                                
Conversion of Stock [Line Items]                                
Amount authorized                       $ 150,000