Name:	glpg_CostShareForGlobalDevelopmentActivities
Namespace Prefix:	glpg_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

The percentage of ratio at which future development cost will be shared before predetermined level.

No definition available.

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

The period of contract for global research and collaboration.

No definition available.

Name:	glpg_GlobalResearchAndDevelopmentCollaborationTerm
Namespace Prefix:	glpg_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Number of entities following intended separation.

No definition available.

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

The number of performance obligations.

No definition available.

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

Line items represent summary of significant transaction.

No definition available.

Name:	glpg_SummaryOfSignificantTransactionLineItems
Namespace Prefix:	glpg_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The amount of cash inflow received as upfront payment.

No definition available.

Name:	glpg_UpfrontPaymentReceived
Namespace Prefix:	glpg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The amount of instruments held by the entity that provide evidence of a residual interest in the assets of another entity after deducting all of its liabilities.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2024-01-01
-Paragraph 55
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_55&doctype=Standard
-URIDate 2024-03-27

Name:	ifrs-full_EquityInstrumentsHeld
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Name:	ifrs-full_NonadjustingEventsAfterReportingPeriodAxis=ifrs-full_AnnouncingOrCommencingImplementationOfMajorRestructuringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	glpg_IfrsTypeOfArrangementAxis=glpg_GileadCollaborationAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_ProductsAndServicesAxis=glpg_FilgotinibDrugLicenseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	ifrs-full_CounterpartiesAxis=glpg_GileadMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	glpg_IfrsScenarioAxis=glpg_OriginalAgreementScenarioMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	glpg_IfrsScenarioAxis=glpg_FirstRevisedAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
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