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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

Percentage of vesting of award under share-based payment arrangement.

No definition available.

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Namespace Prefix:	grfs_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

The maximum number of share options will be granted in a share-based payment arrangement.

No definition available.

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Namespace Prefix:	grfs_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

The vesting life of awards in a share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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Data Type:	xbrli:durationItemType
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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.

No definition available.

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Data Type:	xbrli:stringItemType
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The exercise price of share options granted.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2025-01-01
-Paragraph 47
-Subparagraph a
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2025-en-r&anchor=para_47_a_i&doctype=Standard
-URIDate 2025-03-27

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Namespace Prefix:	ifrs-full_
Data Type:	dtr-2022:perShareItemType
Balance Type:	na
Period Type:	duration

- References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Note Expiry date 2027-01-01
-Name IAS
-Number 1
-IssueDate 2025-01-01
-Paragraph 112
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2025-en-b&anchor=para_112_c&doctype=Standard
-URIDate 2025-03-27

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

The weighted average exercise price of other equity instruments (ie other than share options) granted in a share-based payment arrangement. [Refer: Weighted average [member]]

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

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Data Type:	dtr-2022:perShareItemType
Balance Type:	na
Period Type:	duration

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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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	grfs_IfrsAwardTypeAxis=grfs_StockOptionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_ClassesOfShareCapitalAxis=ifrs-full_OrdinarySharesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	grfs_IfrsVestingAxis=grfs_IfrsShareBasedPaymentArrangementTrancheOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	grfs_IfrsVestingAxis=grfs_IfrsShareBasedPaymentArrangementTrancheTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	grfs_IfrsAwardTypeAxis=grfs_IfrsRestrictedStockUnitsRsusMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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

Name:	ifrs-full_RangeAxis=ifrs-full_BottomOfRangeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: