Provisions - Summary (Details) - EUR (€) € in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Non-current provisions (a)
Provisions for pensions and similar obligations	€ 99	€ 102
Other provisions	20	23
Non-current provisions	119	125
Current provisions (b)
Trade provisions	23	25
Other provisions	12	14
Current provisions	35	39
Total provisions	€ 154	€ 164	€ 165	€ 166

The amount of current trade provisions.

No definition available.

Name:	grfs_CurrentTradeProvisions
Namespace Prefix:	grfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of current provisions, including provisions for employee benefits. [Refer: Provisions]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2027-01-01
-Name IAS
-Number 1
-IssueDate 2025-01-01
-Paragraph 54
-Subparagraph l
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2025-en-b&anchor=para_54_l&doctype=Standard
-URIDate 2025-03-27

+ Details

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

- References

No definition available.

+ Details

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

- Definition

The amount of non-current provisions, including provisions for employee benefits. [Refer: Provisions]

+ References

+ Details

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

- References

No definition available.

+ Details

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

- Definition

The amount of non-current provisions for employee benefits. [Refer: Provisions for employee benefits]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph B9
-Subparagraph e
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_B9_e&doctype=Appendix&subtype=B
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2027-01-01
-Name IAS
-Number 1
-IssueDate 2025-01-01
-Paragraph 78
-Subparagraph d
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2025-en-b&anchor=para_78_d&doctype=Standard
-URIDate 2025-03-27

+ Details

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

- Definition

The amount of non-current provisions other than provisions for employee benefits. [Refer: Non-current provisions]

+ References

+ Details

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

- Definition

The amount of current provisions other than provisions for employee benefits. [Refer: Provisions]

+ References

+ Details

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

- Definition

The amount of liabilities of uncertain timing or amount, including provisions for employee benefits.

+ References

+ Details

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