v3.26.1
Operating expenses - Disclosure of Depreciation, Amortization and Provision Expenses (Details) - EUR (€)
€ in Thousands
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Disclosure Of Operating Expenses [Line Items]      
Amortization expense of intangible assets € (5) € (4) € (1)
Amortization expense of tangible assets (1,607) (1,618) (1,517)
Reversal of provision for disputes and charges 370 212 0
Provision for disputes and charges (50) (206) (163)
Reversal of provision for disputes     0
Total depreciation, amortization and provision expenses (except IAS 19) (1,292) (1,616) (1,682)
Provision for retirement benefit obligations (IAS 19)   (65) (65)
Total Provision for retirement benefit obligations (IAS 19) (80) (65) (65)
Total depreciation, amortization and provision expenses (1,372) (1,681) (1,747)
R&D      
Disclosure Of Operating Expenses [Line Items]      
Amortization expense of intangible assets (4) (3) (1)
Amortization expense of tangible assets (1,263) (1,300) (1,247)
Reversal of provision for disputes and charges 130 160 0
Provision for disputes and charges (17) (6) (47)
Reversal of provision for disputes     0
Total depreciation, amortization and provision expenses (except IAS 19) (1,154) (1,148) (1,295)
Provision for retirement benefit obligations (IAS 19)   (45) (42)
Total Provision for retirement benefit obligations (IAS 19) (53) (45) (42)
Total depreciation, amortization and provision expenses (1,207) (1,193) (1,337)
SG&A      
Disclosure Of Operating Expenses [Line Items]      
Amortization expense of intangible assets (1) (1) 0
Amortization expense of tangible assets (344) (318) (270)
Reversal of provision for disputes and charges 240 52 0
Provision for disputes and charges (33) (200) (116)
Reversal of provision for disputes     0
Total depreciation, amortization and provision expenses (except IAS 19) (138) (467) (387)
Provision for retirement benefit obligations (IAS 19)   (20) (24)
Total Provision for retirement benefit obligations (IAS 19) (26) (20) (24)
Total depreciation, amortization and provision expenses € (164) € (487) € (411)