v3.26.3
FAIR VALUE MEASUREMENT - Inputs (Details)
€ in Thousands, $ in Millions
Jun. 30, 2026
USD ($)
$ / shares
shares
Jun. 30, 2026
EUR (€)
$ / shares
shares
Dec. 31, 2025
EUR (€)
Level 3      
FAIR VALUE MEASUREMENT      
Fair value | €   € 33,597 € 18,143
2025 Convertible Loan Warrants | Share price      
FAIR VALUE MEASUREMENT      
Key inputs 6.26 6.26  
2025 Convertible Loan Warrants | Strike      
FAIR VALUE MEASUREMENT      
Key inputs 4.1956 4.1956  
2025 Convertible Loan Warrants | Volatility      
FAIR VALUE MEASUREMENT      
Key inputs 0.912 0.912  
2025 Convertible Loan Warrants | Risk-free rate      
FAIR VALUE MEASUREMENT      
Key inputs 0.039 0.039  
2025 Convertible Loan Warrants | Level 3      
FAIR VALUE MEASUREMENT      
Fair value | €   € 5,335  
Warrants outstanding | shares 1,250,000 1,250,000  
2025 Convertible Loan Conversion Option | Conversion price      
FAIR VALUE MEASUREMENT      
Key inputs 2.15 2.15  
2025 Convertible Loan Conversion Option | Calibrated rate      
FAIR VALUE MEASUREMENT      
Key inputs 0.797 0.797  
2025 Convertible Loan Conversion Option | CDS spread      
FAIR VALUE MEASUREMENT      
Key inputs 0.148 0.148  
2025 Convertible Loan Conversion Option | Level 3      
FAIR VALUE MEASUREMENT      
Fair value | €   € 3,350  
Principal amount | $ $ 2.5    
XJ Share Price Protection | Share price      
FAIR VALUE MEASUREMENT      
Key inputs 6.26 6.26  
XJ Share Price Protection | Strike      
FAIR VALUE MEASUREMENT      
Key inputs 0.215 0.215  
XJ Share Price Protection | Volatility      
FAIR VALUE MEASUREMENT      
Key inputs 0.912 0.912  
XJ Share Price Protection | Risk-free rate      
FAIR VALUE MEASUREMENT      
Key inputs 0.04 0.04  
XJ Share Price Protection | Level 3      
FAIR VALUE MEASUREMENT      
Fair value | €   € 1,313  
XJ Share Price Protection | Level 3 | XJ Harbour HK limited      
FAIR VALUE MEASUREMENT      
Number of shares held | shares 10,162,575 10,162,575  
2028 Convertible Notes - warrants | Share price      
FAIR VALUE MEASUREMENT      
Key inputs 6.26 6.26  
2028 Convertible Notes - warrants | Strike      
FAIR VALUE MEASUREMENT      
Key inputs 8.01 8.01  
2028 Convertible Notes - warrants | Volatility      
FAIR VALUE MEASUREMENT      
Key inputs 1.117 1.117  
2028 Convertible Notes - warrants | Risk-free rate      
FAIR VALUE MEASUREMENT      
Key inputs 0.04 0.04  
2028 Convertible Notes - warrants | Level 3      
FAIR VALUE MEASUREMENT      
Fair value | €   € 12,195  
2028 Convertible Notes - conversion option | Conversion price      
FAIR VALUE MEASUREMENT      
Key inputs 8.0125 8.0125  
2028 Convertible Notes - conversion option | Calibrated rate      
FAIR VALUE MEASUREMENT      
Key inputs 0.685 0.685  
2028 Convertible Notes - conversion option | CDS spread      
FAIR VALUE MEASUREMENT      
Key inputs 0.248 0.248  
2028 Convertible Notes - conversion option | Level 3      
FAIR VALUE MEASUREMENT      
Fair value | €   € 6,307