v3.25.1
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details)
$ / shares in Units, £ in Thousands
12 Months Ended
Dec. 31, 2024
USD ($)
segment
$ / shares
shares
Dec. 31, 2023
USD ($)
$ / shares
shares
Dec. 31, 2022
USD ($)
$ / shares
shares
Aug. 19, 2021
USD ($)
Aug. 19, 2021
GBP (£)
Accounting Policies [Line Items]          
Investments in debt securities $ 0 $ 0      
Long-lived assets impairment charges $ 0 0 $ 0    
Investment received       $ 46,397,000 £ 38,340
Employee maximum contribution, percentage of monthly salary 8.33%        
Severance pay expenses $ 987,000 $ 1,069,000 $ 1,217,000    
Maximum exercise price of options granted (in USD per share) | $ / shares $ 0.03 $ 0.03 $ 0.03    
Potentially dilutive securities that were excluded from the computation of loss per share (in shares) | shares 7,455,172 2,679,771 2,314,774    
Revenues $ 183,000 $ 1,608,000 $ 0    
Cost of revenues $ 3,681,000 3,270,000 547,000    
Number of operating segments | segment 1        
Number of reportable segments | segment 1        
R&D tax credit benefits $ 5,697,000 769,000 0    
REE Platform Prototypes          
Accounting Policies [Line Items]          
Revenues   943,000      
Cost of revenues   943,000      
SDV Prototypes          
Accounting Policies [Line Items]          
Revenues $ 183,000 665,000 0    
United States          
Accounting Policies [Line Items]          
Matching contribution, percentage of participant annual compensation 4.00%        
Employer expenses related to defined contribution plan $ 81,000 $ 106,000 $ 117,000    
Foreign Plan          
Accounting Policies [Line Items]          
Matching contribution, percentage of participant annual compensation 6.00% 6.00% 6.00%    
Employer expenses related to defined contribution plan $ 515,000 $ 538,000 $ 371,000    
APC          
Accounting Policies [Line Items]          
Non-royalty bearing grants received       12,272,000 10,141
Investment received       49,571,000 40,963
Reduction from research and development expense $ 3,636,000 $ 4,667,000 $ 4,472,000    
UK Government          
Accounting Policies [Line Items]          
Non-royalty bearing grants received       $ 15,002,000 £ 12,397