Share-Based compensation - Black and Scholes model (Details)	6 Months Ended
Jun. 30, 2026 EUR (€) Y € / shares	Jun. 26, 2026 € / shares
Disclosure of terms and conditions of share based payment arrangement
Exercise Price Per Warrant		€ 1.53
Plan 2021 (grant Sept 17 2021)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	2
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.6
Plan 2021 (grant Sept 17 2021) \| Minimum
Disclosure of terms and conditions of share based payment arrangement
Incremental Fair value	0.47
Plan 2021 (grant Sept 17 2021) \| Maximum
Disclosure of terms and conditions of share based payment arrangement
Incremental Fair value	€ 0.59
Plan 2021 (grant Oct 27 2021)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	2
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.6
Plan 2021 (grant Oct 27 2021) \| Minimum
Disclosure of terms and conditions of share based payment arrangement
Incremental Fair value	0.47
Plan 2021 (grant Oct 27 2021) \| Maximum
Disclosure of terms and conditions of share based payment arrangement
Incremental Fair value	€ 0.59
Plan 2021 (grant Feb 21 2022)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	2
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.6
Plan 2021 (grant Feb 21 2022) \| Minimum
Disclosure of terms and conditions of share based payment arrangement
Incremental Fair value	0.47
Plan 2021 (grant Feb 21 2022) \| Maximum
Disclosure of terms and conditions of share based payment arrangement
Incremental Fair value	€ 0.59
Plan 2021 (grant May 14 2022)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	2
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.6
Plan 2021 (grant May 14 2022) \| Minimum
Disclosure of terms and conditions of share based payment arrangement
Incremental Fair value	0.47
Plan 2021 (grant May 14 2022) \| Maximum
Disclosure of terms and conditions of share based payment arrangement
Incremental Fair value	€ 0.58
Plan 2021 (grant March 24 2023)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| Y	2
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.6
Incremental Fair value	€ 0.47
Plan 2022 (grant Feb 01 2024)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	2
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.6
Incremental Fair value	€ 0.46
Plan 2022 (grant Apr 21 2024)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	2
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.6
Incremental Fair value	€ 0.55
Plan 2022 (grant Aug 2 2024)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	2
Exercise price	€ 1.53
Stock price	1.53
Fair value	€ 0.6
Plan 2024 (grant Sep 18 2024)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	2
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.6
Incremental Fair value	€ 0.52
Plan 2024 (grant Nov 25 2024)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	2
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.6
Incremental Fair value	€ 0.53
Plan 2024 (grant Feb 1 2025)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	2
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.6
Incremental Fair value	€ 0.55
Plan 2025 (grant Feb 1 2025)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	2
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.6
Incremental Fair value	€ 0.56
Plan 2025 (grant Mar 14 2025)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	2
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.6
Incremental Fair value	€ 0.56
Plan 2025 (grant Apr 8 2025)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	2
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.6
Incremental Fair value	€ 0.52
Plan 2025 (grant May 5 2025)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	2
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.61
Incremental Fair value	€ 0.48
Plan 2024 (grant Jun 26 2026)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.60%
Risk-free interest rate.	2.71%
Expected life \| €	3
Exercise price	€ 1.53
Stock price	1.53
Fair value	€ 0.75
Plan 2025 (grant Jun 26 2026)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.60%
Risk-free interest rate.	2.71%
Expected life \| €	3
Exercise price	€ 1.53
Stock price	1.53
Fair value	€ 0.75
Plan 2025-2 (grant Jun 26 2026)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.60%
Risk-free interest rate.	2.71%
Expected life \| €	3
Exercise price	€ 1.53
Stock price	1.53
Fair value	€ 0.75
Plan 2025 (grant Sep 6 2025)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	2
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.65
Incremental Fair value	€ 0.45
Plan 2025 (grant Oct 13 2025)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	3
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.67
Incremental Fair value	€ 0.48
2025-2 Plan (grant Jan 18 2026)
Disclosure of terms and conditions of share based payment arrangement
Return Dividend	0.00%
Expected volatility	68.59%
Risk-free interest rate.	2.71%
Expected life \| €	3
Exercise price	€ 1.53
Stock price	1.53
Fair value	0.7
Incremental Fair value	€ 0.41

- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

+ References

No definition available.

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- Definition

The expected volatility of the share price used to calculate the fair value of other equity instrument granted.

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No definition available.

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- Definition

The option life of other equity instrument granted.

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No definition available.

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- Definition

The implied yield currently available on zero-coupon government issues of the country in whose currency the exercise price for other equity instrument granted.

+ References

No definition available.

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- Definition

The exercise price of other equity instrument granted.

+ References

No definition available.

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- Definition

The exercise price of per warrant.

+ References

No definition available.

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- Definition

The percentage of an expected dividend used to calculate the fair value of other equity instrument granted.

+ References

No definition available.

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- Definition

Fair value of other equity instrument granted.

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No definition available.

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Data Type:	dtr-types:perShareItemType
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- Definition

Incremental fair value used as input to the option pricing model to calculate the fair value of share options granted.

+ References

No definition available.

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Period Type:	duration

- Definition

The weighted average share price used as input to the option pricing model to calculate the fair value of other equity instrument granted.

+ References

No definition available.

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