v3.26.1
Note 8 - Convertible Notes Payable at Fair Value - Convertible Debt (Details)
€ in Thousands
Dec. 31, 2025
EUR (€)
Sep. 05, 2025
$ / shares
Sep. 05, 2025
EUR (€)
shares
Dec. 31, 2024
$ / shares
Dec. 31, 2024
EUR (€)
shares
Total Fair Value of Convertible Notes     € 18,471   € 24,035
Measurement Input, Indexed Common Shares [Member]          
Indexed common shares (in shares) | shares     7,718,300   18,537,485
Measurement Input, Share Price [Member]          
Fair value per share (in dollars per share) | $ / shares   $ 2.79   $ 1.24  
Convertible Notes Due December 7, 2023 [Member]          
Fair value convertible notes € 0       € 24,035