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

No definition available.

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

- Definition

The amount of short term liabilities arising from share-based payment transactions. Share-based payment transactions are transactions in which the entity: (a) receives goods or services from the supplier of those goods or services (including an employee) in a share-based payment arrangement; or (b) incurs an obligation to settle the transaction with the supplier in a share-based payment arrangement when another group entity receives those goods or services.

+ References

No definition available.

+ Details

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

- Definition

The amount of long term liabilities arising from share-based payment transactions. Share-based payment transactions are transactions in which the entity: (a) receives goods or services from the supplier of those goods or services (including an employee) in a share-based payment arrangement; or (b) incurs an obligation to settle the transaction with the supplier in a share-based payment arrangement when another group entity receives those goods or services.

+ References

No definition available.

+ Details

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

- Definition

Payments from settlement of cash-settled share-based payment transactions.

+ References

No definition available.

+ Details

Name:	grfs_PaymentsFromSettlementOfCashSettledShareBasedPaymentTransactions
Namespace Prefix:	grfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Threshold business days for computation of average price per share

+ References

No definition available.

+ Details

Name:	grfs_ThresholdBusinessDaysForComputationOfAveragePricePerShare
Namespace Prefix:	grfs_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

Name:	grfs_VestingLifeOfShareBasedAwards
Namespace Prefix:	grfs_
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 members defined in one or many axes of the table.

+ References

No definition available.

+ Details

Name:	ifrs-full_DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
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

+ Details

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

- Definition

The amount of liabilities arising from share-based payment transactions. Share-based payment transactions are transactions in which the entity: (a) receives goods or services from the supplier of those goods or services (including an employee) in a share-based payment arrangement; or (b) incurs an obligation to settle the transaction with the supplier in a share-based payment arrangement when another group entity receives those goods or services. [Refer: Types of share-based payment arrangements [domain]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2025-01-01
-Paragraph 51
-Subparagraph b
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2025-en-r&anchor=para_51_b_i&doctype=Standard
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 34
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_34_b&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 34
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_34_b&doctype=Standard
-URIDate 2025-03-27

+ Details

Name:	ifrs-full_LiabilitiesFromSharebasedPaymentTransactions2011
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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

- Details

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

- Details

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

- Details

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

- Details

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

Employee Benefits - Cash-settled share-based payment plan - Narrative (Details) - Cash-settled share-based payment plan - EUR (€) € in Millions	1 Months Ended		12 Months Ended
	May 31, 2025	May 31, 2023	Dec. 31, 2025	Dec. 31, 2024
Employee Benefits
Expense from cash-settled share-based payment transactions			€ 1	€ 1
Ordinary shares
Employee Benefits
Threshold Business Days for Computation of Average Price Per Share		5 days
Restricted stock units (RSUs)
Employee Benefits
Vesting Period		4 years
Liabilities from share-based payment transactions				3
Payments from settlement of cash-settled share-based payment transactions	€ 2
Total short-term Trading creditors and other account payable				2
Long-term in provisions			€ 2	€ 1
Restricted stock units (RSUs) \| Tranche One
Employee Benefits
Percentage of award vesting rights	50.00%	50.00%
Restricted stock units (RSUs) \| Tranche Two
Employee Benefits
Percentage of award vesting rights		50.00%