Trade Receivables and Other Current Assets and Receivables - Trade Receivables (Details) - EUR (€) € in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Trade Receivables and Other Current Assets and Receivables [Line Items]
Trade receivables	€ 4,000	€ 48	€ 4
Average payment period for trade receivables	30 days
Milestone payments received	€ 4,000
AbbVie
Trade Receivables and Other Current Assets and Receivables [Line Items]
Milestone payments received	4,000		0
3 months or less
Trade Receivables and Other Current Assets and Receivables [Line Items]
Trade receivables	€ 4,000	€ 48	€ 4

The amount of current trade receivables. [Refer: Trade receivables]

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 78
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_78_b&doctype=Standard
-URIDate 2021-03-24

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 68
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_68&doctype=Standard
-URIDate 2021-03-24

+ Details

Name:	ifrs-full_CurrentTradeReceivables
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the cumulative amount of research funding received in a collaborative arrangement.

+ References

No definition available.

+ Details

Name:	iva_CollaborativeArrangementMilestonePaymentsReceived
Namespace Prefix:	iva_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the average payment period for trade receivables.

+ References

No definition available.

+ Details

Name:	iva_CurrentTradeReceivablesAveragePaymentPeriod
Namespace Prefix:	iva_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

+ References

No definition available.

+ Details

Name:	iva_TradeReceivablesAndOtherCurrentAssetsAndReceivablesLineItems
Namespace Prefix:	iva_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	iva_IfrsCollaborativeArrangementAndArrangementOtherThanCollaborativeAxis=iva_ResearchCollaborationWithAbbvieMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_MaturityAxis=ifrs-full_NotLaterThanThreeMonthsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: