v3.25.1

Equity Investments - Roll-forward (Details) - EUR (€) | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023
Disclosure of financial assets [line items] |  |
Fair value adjustment of the year | € 2,500,000 | € 0
Equity instruments |  |
Disclosure of financial assets [line items] |  |
Cost at January 1 | 13,575,000 |
Cost at December 31 | 52,941,000 | 13,575,000
Fair value adjustment at January 1 | (390,000) |
Fair value adjustment of the year | 2,485,000 | (390,000)
Fair value adjustment at December 31 | 2,095,000 | (390,000)
Equity instruments | Gross amount before fair value adjustment. |  |
Disclosure of financial assets [line items] |  |
Cost at January 1 | 13,965,000 |
Acquisition of the year | 36,880,000 | 13,965,000
Cost at December 31 | € 50,845,000 | € 13,965,000

X
- Definition The increase in equity investment due to acquisition of the year. + References No definition available. + Details
Name: | glpg_AcquisitionInEquityInstrumentOfYear
Namespace Prefix: | glpg_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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

X
- Definition 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. + References 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 + Details
Name: | ifrs-full_EquityInstrumentsHeld
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The gains (losses) including exchange differences recognised in other comprehensive income on the fair value measurement of assets. [Refer: At fair value [member]; Other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 13 -IssueDate 2024-01-01 -Paragraph 93 -Subparagraph e -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=13&code=ifrs-tx-2024-en-r&anchor=para_93_e_ii&doctype=Standard -URIDate 2024-03-27 + Details
Name: | ifrs-full_GainsLossesRecognisedInOtherComprehensiveIncomeFairValueMeasurementAssets
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition A component of equity representing the reserve of gains and losses on financial assets measured at fair value through other comprehensive income. [Refer: Financial assets measured at fair value through other comprehensive income; Other comprehensive income] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 78 -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_78_e&doctype=Standard -URIDate 2024-03-27 + Details
Name: | ifrs-full_ReserveOfGainsAndLossesOnFinancialAssetsMeasuredAtFairValueThroughOtherComprehensiveIncome
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | ifrs-full_ClassesOfFinancialAssetsAxis=ifrs-full_EquityInvestmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis=ifrs-full_GrossCarryingAmountMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |