Maximum number of awards issuable under plan.

No definition available.

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- Definition

The percentage of instruments granted in share-based payment arrangement.

+ References

No definition available.

+ Details

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- Definition

The number of individuals in the potential beneficiary group.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of senior executives in the potential beneficiary group.

+ References

No definition available.

+ Details

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Namespace Prefix:	grfs_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of share-based compensation recognized in equity.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The percentage of target for performance thresholds and payout curves for deliveries under the share-based arrangement.

+ References

No definition available.

+ Details

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Namespace Prefix:	grfs_
Data Type:	dtr-types:percentItemType
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

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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

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- Details

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- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_RangeAxis=ifrs-full_TopOfRangeMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Data Type:	na
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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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Employee Benefits - Stock Incentive plan (Details) - Stock Incentive Plan [Member] € in Millions	Jun. 05, 2025 shares director individual	Dec. 31, 2025 EUR (€)
Disclosure of terms and conditions of share-based payment arrangement [line items]
Potential beneficiary group, number of senior executives \| director	11
Potential beneficiary group, number of individuals \| individual	47
Vesting Period	3 years
Share-based compensation, amount recognized in equity. \| €		€ 3
Maximum number of awards issuable under plan \| shares	1,032,671
Minimum
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share-based payment arrangement, threshold target percentage	0.00%
Maximum
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share-based payment arrangement, threshold target percentage	150.00%
Senior executives \| Performance shares
Disclosure of terms and conditions of share-based payment arrangement [line items]
Percentage of instruments granted in share-based payment arrangement	100.00%
Other participants \| Performance shares
Disclosure of terms and conditions of share-based payment arrangement [line items]
Percentage of instruments granted in share-based payment arrangement	65.00%
Other participants \| Fidelity Shares
Disclosure of terms and conditions of share-based payment arrangement [line items]
Percentage of instruments granted in share-based payment arrangement	35.00%