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The amount of advances received representing contract liabilities for performance obligations satisfied at a point in time. [Refer: Contract liabilities; Performance obligations satisfied at point in time [member]]

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The amount of instruments issued by the entity that represent indebtedness.

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The amount of deferred tax liabilities or assets. [Refer: Deferred tax liabilities; Deferred tax assets]

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The amount of expense relating to fees and commissions.

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The amount of assistance by government in the form of transfers of resources to an entity in return for past or future compliance with certain conditions relating to the operating activities of the entity, recognised as deferred income. They exclude those forms of government assistance that cannot reasonably have a value placed upon them and transactions with government that cannot be distinguished from the normal trading transactions of the entity. [Refer: Deferred income other than contract liabilities; Government [member]]

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The amount of deferred tax assets net of deferred tax liabilities, when the absolute amount of deferred tax assets is greater than the absolute amount of deferred tax liabilities. [Refer: Deferred tax assets; Deferred tax liabilities]

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The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

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The number of shares issued by the entity.

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

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Loans and Borrowings - Additional Information (Details)														1 Months Ended				6 Months Ended		12 Months Ended
Loans and Borrowings - Additional Information (Details)	Apr. 06, 2022 EUR (€)	Mar. 02, 2022 EUR (€)	Dec. 22, 2021 shares	Nov. 26, 2021 EUR (€)	Sep. 01, 2021 EUR (€) shares	Jul. 23, 2021 EUR (€)	Jul. 20, 2021 EUR (€)	Jun. 29, 2021 EUR (€)	Jun. 24, 2021 EUR (€) bank	Jun. 20, 2021	Feb. 04, 2021 EUR (€) shares	Oct. 16, 2017 EUR (€) euroPerBond oCEANE	Dec. 31, 2014 EUR (€)	Aug. 31, 2021 bond	Mar. 31, 2021 bond	Feb. 28, 2021 bond	Jan. 31, 2021 bond	Jun. 30, 2022 EUR (€) euroPerBond installment oCEANE	Jun. 30, 2021 EUR (€)	Dec. 31, 2021 EUR (€)	Dec. 31, 2020 EUR (€)	Oct. 16, 2025 EUR (€)	Nov. 23, 2021 EUR (€)	Apr. 06, 2021 shares	Mar. 02, 2021 shares	Dec. 23, 2008 EUR (€)
Disclosure of detailed information about borrowings [line items]
Increase Decrease Through Capital Increase																		€ 0		€ 28,268,000	€ 37,064,000
Fee and commission expense																		2,303,000	€ 745,000
Deferred tax liability (asset)																		647,000		602,000
Deferred tax liabilities																		647,000		602,000
Deferred tax assets																		€ 0		0
Number of biannual installments \| installment																		2
+ Proceeds from new loans and borrowings net of issue costs																		€ 0	€ 10,905,000
Number of shares issued during period (in shares) \| shares			3,985,239
Bonds after OCEANEs buyback
Disclosure of detailed information about borrowings [line items]
Nominal amount of the loan																		€ 56,940,000
BPI FRANCE - IT-DIAB
Disclosure of detailed information about borrowings [line items]
Discounted rate													5.19%
BPI FRANCE - IT-DIAB \| Conditional
Disclosure of detailed information about borrowings [line items]
Advances received																										€ 3,229,000
BPI FRANCE - IT-DIAB \| Non-repayable
Disclosure of detailed information about borrowings [line items]
Government grants																										€ 3,947,000
OCEANE
Disclosure of detailed information about borrowings [line items]
Number of debt instruments issued \| oCEANE												6,081,081
Nominal value per unit (in EUR per bond) \| euroPerBond												29.60
Aggregate nominal amount												€ 180,000,000										€ 57,000,000
Conversion / exchange premium																	550.00%		100.00%
New O C E AN E shares (in shares) \| bond														10,000	216,591	483,330	552,238
Increase Decrease Through Capital Increase	€ 297,812,500	€ 664,578,750			€ 13,750,000						€ 759,327,250
New shares created (in shares) \| shares					55,000																			1,191,250	2,658,312
Number of shares issued during period (in shares) \| shares											3,037,309
OCEANE \| Bonds after OCEANEs buyback
Disclosure of detailed information about borrowings [line items]
Number of debt instruments issued \| oCEANE												3,185,821						1,923,662
Nominal value per unit (in EUR per bond) \| euroPerBond												29.60						29.60
Effective interest rate												8.80%						8.80%
Nominal amount of the loan												€ 94,300,301.6						€ 56,940,395.2		€ 56,940,000
Conditional advances \| BPI FRANCE - IT-DIAB \| Additional Payments
Disclosure of detailed information about borrowings [line items]
Maximum amount to be paid if any further amounts to be paid as conditional advance													€ 14,800,000
Pret Garanti Par L etat (PGE) Bancaire
Disclosure of detailed information about borrowings [line items]
Nominal amount of the loan									€ 11,000,000
Number of French banks \| bank									4
Debt instrument, initial term (in years)									1 year
Repayment options, up to (in years)									6 years
+ Proceeds from new loans and borrowings net of issue costs								€ 10,919,000
Proportion of loan guaranteed by the French government (in percent)							90.00%
BPI PGE [Member]
Disclosure of detailed information about borrowings [line items]
Nominal amount of the loan							€ 2,000,000
Debt instrument, initial term (in years)										1 year
Repayment options, up to (in years)										6 years
+ Proceeds from new loans and borrowings net of issue costs						€ 1,985,000
Proportion of loan guaranteed by the French government (in percent)							90.00%
Subsidized Loan
Disclosure of detailed information about borrowings [line items]
Nominal amount of the loan																							€ 2,250,000
Debt instrument, initial term (in years)				6 years
+ Proceeds from new loans and borrowings net of issue costs				€ 2,250,000
Convertible loans
Disclosure of detailed information about borrowings [line items]
Convertible bond, yearly interest																		€ 1,993,000