The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents]

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The amount of long-term deposits held by the entity.

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The cash inflow from borrowings obtained. [Refer: Borrowings]

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The cash inflow from the issuing of ordinary shares. [Refer: Ordinary shares [member]]

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The amount of short-term deposits held by the entity that are not classified as cash equivalents. [Refer: Cash equivalents]

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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.

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Accounting principles - Going concern (Details) € in Thousands, $ in Millions		1 Months Ended	7 Months Ended	12 Months Ended
	Jan. 18, 2024 EUR (€)	Oct. 31, 2023 EUR (€)	Aug. 02, 2024 USD ($)	Dec. 31, 2023 EUR (€)	Dec. 31, 2022 EUR (€)	Dec. 31, 2021 EUR (€)	Dec. 31, 2020 EUR (€)
Going Concern
Cash and cash equivalents				€ 26,918	€ 86,736	€ 86,553	€ 105,687
Short-term deposits				10
Subscription of borrowings					€ 30,209
Long-term deposit forward contract
Going Concern
Long-term deposit		€ 9,000		€ 9,000
Period of long-term deposit		2 years		2 years
Cowen ATM program \| Maximum \| Forecast
Going Concern
Aggregate offering price \| $			$ 58.0
Drawdown of borrowings \| Finance contract with EIB, Tranche B
Going Concern
Subscription of borrowings	€ 25,000