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Period Type:	duration

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 2
-IssueDate 2025-01-01
-Paragraph 45
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2025-en-r&anchor=para_45&doctype=Standard
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2025-01-01
-Paragraph 47
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2025-en-r&anchor=para_47_b&doctype=Standard
-URIDate 2025-03-27

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Period Type:	duration

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

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:decimalItemType
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The number of other equity instruments (ie other than share options) forfeited in a share-based payment arrangement.

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:decimalItemType
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Period Type:	duration

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

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

The weighted average fair value at the measurement date of granted equity instruments other than share options. [Refer: Weighted average [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2025-01-01
-Paragraph 47
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2025-en-r&anchor=para_47_b&doctype=Standard
-URIDate 2025-03-27

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Period Type:	instant

Weighted average fair value at measurement date other equity instruments forfeited.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Weighted average fair value at measurement date other equity instruments outstanding.

No definition available.

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Namespace Prefix:	otly_
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Balance Type:	na
Period Type:	instant

Weighted average fair value at measurement date other equity instruments vested

No definition available.