Share-based payments - Disclosure of breakdown of the compensation expenses (Details) - EUR (€) € in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Disclosure of terms and conditions of share-based payment arrangement [line items]
Total	€ (5,372)	€ (6,216)
BCEs
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share-based compensation expense	0	(28)
BSAs
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share-based compensation expense	(65)	0
AGAs
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share-based compensation expense	(4,623)	(5,727)
Social taxes related to AGAs	€ (683)	€ (461)

Expense From Equity-Settled Share-Based Payment Transactions, Social Taxes

No definition available.

Name:	abvx_ExpenseFromEquitySettledShareBasedPaymentTransactionsSocialTaxes
Namespace Prefix:	abvx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of expense arising from equity-settled share-based payment transactions in which the goods or services received did not qualify for recognition as assets. [Refer: Expense from share-based payment transactions]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2024-01-01
-Paragraph 51
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2024-en-r&anchor=para_51_a&doctype=Standard
-URIDate 2024-03-27

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of expense arising from share-based payment transactions in which the goods or services received did not qualify for recognition as assets.

+ References

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_TypesOfSharebasedPaymentArrangementsAxis=abvx_ShareSubscriptionWarrantsBSAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_TypesOfSharebasedPaymentArrangementsAxis=abvx_FreeSharesAGAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: