v3.25.1

Summary of significant transactions - Transfer of Jyseleca Business To Alfasigma (Details) - Jyseleca business, classified as held for sale |  |  |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Jan. 31, 2024 EUR (€) position country | Dec. 30, 2023 item | Oct. 30, 2023 country | Jan. 31, 2024 EUR (€) item country | Dec. 31, 2024 EUR (€)
Summary of significant transaction |  |  |  |  |
Number of positions in European countries agreed to transfer | 400 | 400 |  | 400 |
Number of European countries in which positions has been agreed to transfer | country | 14 |  | 14 | 14 |
Upfront payment to receive. |  |  |  | € 50,000,000 | € 50,000,000
Cash and working capital |  |  |  | 9,800,000 |
Potential Milestone Payments to receive | € 120,000,000 |  |  | € 120,000,000 | 120,000,000
Commitments Related To Development Activities. |  |  |  |  | 25,000,000
Contributions to Alfasigma for Jyseleca related development |  |  |  |  | € 15,000,000

X
- Definition The amount of cash inflow for cash and working capital. + References No definition available. + Details
Name: | glpg_CashAndWorkingCapitalPaymentReceived
Namespace Prefix: | glpg_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Commitments to Alfasigma related to development activities. + References No definition available. + Details
Name: | glpg_CommitmentsRelatedToDevelopmentActivities.
Namespace Prefix: | glpg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Number of European countries agreed in which positions has been agreed to transfer, pursuant to an arrangement. + References No definition available. + Details
Name: | glpg_NumberOfEuropeanCountriesInWhichPositionsHasBeenAgreedToTransfer
Namespace Prefix: | glpg_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of positions agreed to transfer, pursuant to an arrangement. + References No definition available. + Details
Name: | glpg_NumberOfPositionsAgreedToTransfer
Namespace Prefix: | glpg_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Payments to Alfasigma for Jyseleca related development activities. + References No definition available. + Details
Name: | glpg_PaymentsRelatedToDevelopmentActivities.
Namespace Prefix: | glpg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Line items represent summary of significant transaction. + References No definition available. + Details
Name: | glpg_SummaryOfSignificantTransactionLineItems
Namespace Prefix: | glpg_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of cash inflow received as upfront payment. + References No definition available. + Details
Name: | glpg_UpfrontPaymentReceived
Namespace Prefix: | glpg_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of upfront payments receivable. + References No definition available. + Details
Name: | glpg_UpfrontPaymentsReceivable
Namespace Prefix: | glpg_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | ifrs-full_ContinuingAndDiscontinuedOperationsAxis=glpg_JyselecaBusinessClassifiedAsHeldForSaleMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |