v3.26.1
REVENUE AND GRANT INCOME RECOGNITION - Schedule of Revenues and Grant Income by Customer Type (Details) - USD ($)
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Disaggregation of Revenue [Line Items]        
Services revenue [1] $ 50,119,000 $ 16,919,000 $ 90,025,000 $ 34,010,000
Grant income 4,482,000 4,585,000 7,999,000 8,298,000
Total revenues and grant income 54,601,000 21,504,000 98,024,000 42,308,000
Cost-based        
Disaggregation of Revenue [Line Items]        
Services revenue 45,590,000 14,029,000 83,004,000 27,681,000
Grant income 4,482,000 4,585,000 7,999,000 8,298,000
Total revenues and grant income 50,072,000 18,614,000 91,003,000 35,979,000
Fixed fee        
Disaggregation of Revenue [Line Items]        
Total revenues and grant income 839,000 1,048,000 1,174,000 1,988,000
Cost plus fixed fee        
Disaggregation of Revenue [Line Items]        
Total revenues and grant income 804,000 1,442,000 1,247,000 3,550,000
Time & materials        
Disaggregation of Revenue [Line Items]        
Total revenues and grant income 2,886,000 400,000 4,600,000 791,000
DOE        
Disaggregation of Revenue [Line Items]        
Services revenue 43,195,000 11,172,000 78,686,000 22,660,000
Grant income 4,482,000 4,585,000 7,999,000 8,298,000
Total revenues and grant income 47,677,000 15,757,000 86,685,000 30,958,000
Department of War        
Disaggregation of Revenue [Line Items]        
Total revenues and grant income 1,642,000 1,541,000 2,421,000 3,491,000
Commercial        
Disaggregation of Revenue [Line Items]        
Total revenues and grant income $ 5,282,000 $ 4,206,000 $ 8,918,000 $ 7,859,000
[1] Includes related party revenue of $2.4 million and $2.3 million for the three months ended June 30, 2026 and 2025, respectively, and $4.3 million and $5.0 million for the six months ended June 30, 2026 and 2025, respectively.