v3.25.1

Deferred tax - Narrative (Details) - EUR (€) | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | --- | ---
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Amount of tax attributes and deductible temporary differences | € 1,984,900,000 | € 1,722,200,000 | € 1,882,500,000
Amount of unused tax losses carried forward | 862,000,000 | 798,700,000 |
Deferred tax assets | 1,474,000 | 1,126,000 |
Expiry between 2028 and 2034 |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Amount of unused tax losses carried forward | 1,100,000 |  |
Subsidiary companies operating on a cost plus basis |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred tax assets | 1,500,000 | 1,100,000 |
Galapagos Nv (Belgium) |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Amount of unused tax losses carried forward | 822,400,000 | 757,900,000 |
Investment Deduction |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Amount of tax attributes and deductible temporary differences | 1,000,000 | 1,000,000 | 1,000,000
Innovation Income, dividend received deduction and investment deduction |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Amount of tax attributes and deductible temporary differences | 566,400,000 | 410,000,000 | 365,900,000
Due to innovation income deduction |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Amount of tax attributes and deductible temporary differences | 534,400,000 | 390,300,000 | 346,200,000
Unrecognized Deferred Tax Assets Excluding Innovation Income Reduction |  | 326,800,000 |
All losses including innovation income deduction [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Unrecognized Deferred Tax Assets | 490,100,000 | 424,400,000 |
Dividend received deduction carried forward to be offset against future income Screen reader support enabled. |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Amount of tax attributes and deductible temporary differences | 31,000,000 | 18,700,000 | 18,700,000
Consolidated Tax Losses Carried Forward And Deductible Temporary DIfferences [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Amount of tax attributes and deductible temporary differences | € 1,418,500,000 | € 1,312,200,000 | € 1,516,600,000

X
- Definition The amounts of unrecognized deferred tax asset. + References No definition available. + Details
Name: | glpg_UnrecognizedDeferredTaxAssets
Namespace Prefix: | glpg_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amounts of unrecognized deferred tax asset excluding the unrecognized deferred tax asset from innovation income reduction. + References No definition available. + Details
Name: | glpg_UnrecognizedDeferredTaxAssetsExcludingInnovationIncomeReduction
Namespace Prefix: | glpg_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount of deductible temporary differences for which no deferred tax asset is recognised in the statement of financial position. [Refer: Temporary differences [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2024-01-01 -Paragraph 81 -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2024-en-r&anchor=para_81_e&doctype=Standard -URIDate 2024-03-27 + Details
Name: | ifrs-full_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognised
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Definition The amounts of income taxes recoverable in future periods in respect of: (a) deductible temporary differences; (b) the carryforward of unused tax losses; and (c) the carryforward of unused tax credits. [Refer: Temporary differences [member]; Unused tax credits [member]; Unused tax losses [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2024-01-01 -Paragraph 81 -Subparagraph g -Clause i -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2024-en-r&anchor=para_81_g_i&doctype=Standard -URIDate 2024-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 54 -Subparagraph o -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_54_o&doctype=Standard -URIDate 2024-03-27 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 56 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_56&doctype=Standard -URIDate 2024-03-27 + Details
Name: | ifrs-full_DeferredTaxAssets
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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_DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of unused tax losses for which no deferred tax asset is recognised in the statement of financial position. [Refer: Unused tax losses [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2024-01-01 -Paragraph 81 -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=12&code=ifrs-tx-2024-en-r&anchor=para_81_e&doctype=Standard -URIDate 2024-03-27 + Details
Name: | ifrs-full_UnusedTaxLossesForWhichNoDeferredTaxAssetRecognised
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | ifrs-full_MaturityAxis=glpg_LaterThanOneYearAndNotLaterThanFifteenYearsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_SignificantInvestmentsInSubsidiariesAxis=glpg_SubsidiaryCompaniesOperatingOnCostPlusBasisForWhomDeferredTaxAssetIsRecognizedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_SignificantInvestmentsInSubsidiariesAxis=glpg_GalapagosNvBelgiumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=glpg_InvestmentDeductionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=glpg_InnovationIncomeDeductionAndInvestmentDeductionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=glpg_DueToInnovationIncomeDeductionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=glpg_AllLossesIncludingInnovationIncomeDeductionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=glpg_DividendReceivedDeductionCarriedForwardToBeOffsetAgainstFutureIncomeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis=glpg_ConsolidatedTaxLossesCarriedForwardAndDeductibleTemporaryDifferencesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |