v3.20.1

Current financial investments (Details) - 12 months ended Dec. 31, 2019 € in Thousands, $ in Millions | USD ($) | EUR (€)
--- | --- | ---
Current financial investments |  |
Current financial investments | € |  | € 3,919,216
Short term bond fund minimum investment period | 6 months |
Current financial investments held in USD | $ | $ 850.5 |

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- Definition Current Financial Investments [Abstract] + References No definition available. + Details
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Namespace Prefix: | glpg_
Data Type: | xbrli:stringItemType
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- Definition The carrying balance of current financial investments subject to foreign currency exchange gain or loss in our financial results. + References No definition available. + Details
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- Definition Represents the short term bond fund minimum recommended investment period. + References No definition available. + Details
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Namespace Prefix: | glpg_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition The amount of current investments. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_55&doctype=Standard -URIDate 2019-03-27 + Details
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