The expected volatility of the share price used to calculate the fair value of the share options granted. Expected volatility is a measure of the amount by which a price is expected to fluctuate during a period. The measure of volatility used in option pricing models is the annualised standard deviation of the continuously compounded rates of return on the share over a period of time.

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The option life of share options granted.

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The implied yield currently available on zero-coupon government issues of the country in whose currency the exercise price for share options granted is expressed, with a remaining term equal to the expected term of the option being valued (based on the option's remaining contractual life and taking into account the effects of expected early exercise). [Refer: Government [member]]

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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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The number of other equity instruments (ie other than share options) granted in a share-based payment arrangement.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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The weighted average exercise price of other equity instruments (ie other than share options) outstanding in a share-based payment arrangement. [Refer: Weighted average [member]]

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The weighted average fair value at the measurement date of granted equity instruments other than share options. [Refer: Weighted average [member]]

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Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

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Period which the right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Subscription premium price per share of other equity instruments granted in share-based payment arrangement.

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Shareholders' Equity - Characteristics of BSA share warrant plans (Details)									12 Months Ended
	Apr. 16, 2021 EUR (€) € / shares shares	Apr. 16, 2021 EUR (€) € / shares shares	Apr. 16, 2021 EUR (€) item € / shares shares	Apr. 16, 2021 EUR (€) Y € / shares shares	Mar. 09, 2020 EUR (€) Y item € / shares shares	Jun. 28, 2019 Y item € / shares shares	Dec. 14, 2018 EUR (€) item Y € / shares shares	May 29, 2017 EUR (€) item Y € / shares shares	Dec. 31, 2020 € / shares	Dec. 31, 2022 € / shares	Dec. 31, 2021 € / shares	Jun. 26, 2019 EUR (€)
BSA - 2017 plan
Disclosure of terms and conditions of share-based payment arrangement [line items]
Subscription premium price per share (€)								€ 0.534
Exercise price (in euros)									€ 6.67	€ 6.67	€ 6.67
BSA - 2017 plan \| Tranche one
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting period								1 year
BSA - 2017 plan \| Tranche two
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting period								2 years
BSA - 2017 plan \| Tranche three
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting period								3 years
BSA - 2018 plan
Disclosure of terms and conditions of share-based payment arrangement [line items]
Exercise price (in euros)									€ 6.07	6.07	6.07
BSA 2018-1
Disclosure of terms and conditions of share-based payment arrangement [line items]
Issued \| item							126,000
Number of shares per BSA \| shares							1
Subscription premium price per share (€)							€ 0.48
Exercise price (in euros)							€ 6.067
Fair value per BSA at grant date (€) \| €							€ 1.98
Expected volatility							40.00%
Average life (years) \| Y							6
Risk free rate							0.30%
BSA 2018-1 \| Top Of range
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting period							3 years
BSA 2018-1 \| Bottom of range [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting period							1 year
BSA 2019
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting period						1 year
Issued \| item						10,000
Number of shares per BSA \| shares						1
Subscription premium price per share (€)						€ 0.18
Exercise price (in euros)						€ 2.20
Fair value per BSA at grant date (€) \| €												€ 0.48
Expected volatility						40.00%
Average life (years) \| Y						5.5
Risk free rate						0.33%
BSA 2019 bis
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting period					1 year
Issued					10,000				10,000
Number of shares per BSA \| shares					1
Subscription premium price per share (€)					€ 0.29
Exercise price (in euros)					€ 3.68				€ 3.68	3.68	3.68
Fair value per BSA at grant date (€) \| €					€ 0.90
Expected volatility					40.00%
Average life (years) \| Y					6
Risk free rate					0.00%
BSA 2019 ter
Disclosure of terms and conditions of share-based payment arrangement [line items]
Issued					36,000				36,000
Number of shares per BSA \| shares					1
Subscription premium price per share (€)					€ 0.29
Exercise price (in euros)					€ 3.68				€ 3.68	€ 3.68	€ 3.68
Fair value per BSA at grant date (€) \| €					€ 0.90
Expected volatility					40.00%
Average life (years) \| Y					6
Risk free rate					0.00%
BSA 2019 ter \| Top Of range
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting period					3 years
BSA 2019 ter \| Bottom of range [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting period					1 year
BSA 2021 [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting period	3 years
Issued		50,000	50,000
Number of shares per BSA \| shares	1	1	1	1
Subscription premium price per share (€)	€ 2.45	€ 2.45	€ 2.45	€ 2.45
Exercise price (in euros)	€ 11.74	€ 11.74	€ 11.74	€ 11.74
Expected volatility		64.00%
Average life (years) \| Y				5
Risk free rate		0.60%
BSA 2021 [Member] \| Bottom of range [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Fair value per BSA at grant date (€) \| €	€ 3.0	€ 3.0	€ 3.0	€ 3.0
BSA - 2017
Disclosure of terms and conditions of share-based payment arrangement [line items]
Issued \| item								195,000
Number of shares per BSA \| shares								1
Exercise price (in euros)								€ 6.675
Fair value per BSA at grant date (€) \| €								€ 2.47
Expected volatility								40.00%
Average life (years) \| Y								6
Risk free rate								0.22%
BSA - 2017 \| Top Of range
Disclosure of terms and conditions of share-based payment arrangement [line items]
Fair value per BSA at grant date (€) \| €	€ 3.2	€ 3.2	€ 3.2	€ 3.2