Non-cash stock-based compensation - Summary of Information on Warrants Activity (Detail) - Non Employee Warrants [Member]	6 Months Ended	12 Months Ended
Jun. 30, 2023 € / shares	Dec. 31, 2022 € / shares	Dec. 31, 2021 € / shares
Disclosure Of Number And Weighted Average Exercise Prices Of Share Options and awards [Line Items]
Option exercisable, beginning balance	896,225	896,225
Option exercisable, ending balance	896,225	896,225	896,225
Weighted- average exercise price per share, beginning balance	€ 27.18	€ 27.18
Weighted- average exercise price per share, ending balance	€ 27.18	€ 27.18	€ 27.18
Option outstanding, beginning balance	896,225	896,225
Option outstanding, ending balance	896,225	896,225	896,225
Weighted average exercise price per share, beginning balance	€ 27.18	€ 27.18
Weighted average exercise price per share, ending balance	€ 27.18	€ 27.18	€ 27.18
Remaining Average Useful Life	2 years 9 months 18 days	3 years 3 months 18 days	4 years 3 months 18 days

Disclosure Of Number And Weighted Average Exercise Prices Of Share Options and awards [Line Items]

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- Definition

The number of share options outstanding in a share-based payment arrangement.

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The number of share options exercisable in a share-based payment arrangement.

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The weighted average exercise price of share options exercisable in a share-based payment arrangement. [Refer: Weighted average [member]]

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The weighted average exercise price of share options outstanding in a share-based payment arrangement. [Refer: Weighted average [member]]

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The weighted average remaining contractual life of outstanding share options. [Refer: Weighted average [member]]

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