Name:	glpg_IfrsShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod
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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The number of calendar days period preceding the reporting period of other equity instrument for calculate the value of weighted average price of entity share traded on stock-exchange.

No definition available.

Name:	glpg_NumberOfCalendarDaysPeriodPrecedingReportingPeriodForCalculateValueOfWeightedAveragePriceOfEntityShareTradedOnStockExchange
Namespace Prefix:	glpg_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

The number of calendar days period preceding the relevant vesting date of other equity instrument for calculate the value of weighted average price of entity share traded on stock-exchange.

No definition available.

Name:	glpg_NumberOfCalendarDaysPeriodPrecedingVestingDateForCalculateValueOfWeightedAveragePriceOfEntityShareTradedOnStockExchange
Namespace Prefix:	glpg_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Number of securities into which each restricted stock or right may be converted. For example, but not limited to, each restricted stock or right may be converted into two shares.

No definition available.

Name:	glpg_NumberOfSecuritiesCalledByEachRestrictedStockOrRight
Namespace Prefix:	glpg_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

The percentage of other equity instruments vested for share based payment transaction.

No definition available.

Name:	glpg_PercentageOfOtherEquityInstrumentsVested
Namespace Prefix:	glpg_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

The percentage of other equity instruments vested in certain period for share based payment transaction.

No definition available.

Name:	glpg_PercentageOfOtherEquityInstrumentsVestedInCertainPeriod
Namespace Prefix:	glpg_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

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.

Name:	ifrs-full_DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

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]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2024-01-01
-Paragraph 51
-Subparagraph b
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2024-en-r&anchor=para_51_b_i&doctype=Standard
-URIDate 2024-03-27

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

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

Name:	glpg_VestingPercentageAxis=glpg_ShareBasedCompensationAwardVestingPercentagePortionOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	glpg_VestingPercentageAxis=glpg_ShareBasedCompensationAwardVestingPercentagePortionTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	glpg_IfrsVestingAxis=glpg_IfrsShareBasedCompensationAwardTrancheOneMember
Namespace Prefix:
Data Type:	na
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