General Information - Revision of comparative figures (Details) - EUR (€) € in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024	Dec. 31, 2023
Equity attributable to owners of the Company	€ 66,983		€ 66,983		€ 88,560
Deferred income	44,435		44,435		51,371
Revenue	3,817	€ 6,305	8,336	€ 10,755
Result for the year	(12,179)	(2,692)	(22,258)	(10,350)
Equity	66,983	32,854	66,983	32,854	88,560	€ 41,390
Changes in working capital	1,178	4,614	7,900	13,838
Accumulated Deficit
Result for the year			(22,258)	(10,350)
Equity	€ (447,773)	€ (410,553)	€ (447,773)	€ (410,553)	€ (427,158)	€ (400,850)

The amount of residual interest in the assets of the entity after deducting all its liabilities.

The total of income less expenses from continuing and discontinued operations, excluding the components of other comprehensive income. [Refer: Other comprehensive income]

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+ Details