Price of a single share of the company's stock.

No definition available.

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Period Type:	instant

- Definition

Increase in Share Capital and issuance premium due to Issuance of Warrants

+ References

No definition available.

+ Details

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- Definition

The number of other equity instruments (ie other than share options) exercised in a share-based payment arrangement.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The weighted average exercise price of other equity instruments (i.e. other than share options) exercised in a share-based payment arrangement. [Refer: Weighted average [member]]

+ References

No definition available.

+ Details

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

+ References

No definition available.

+ Details

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- Definition

The number of shares issued by the entity.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 106
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_106_d&doctype=Standard
-URIDate 2019-03-27

+ Details

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Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	glpg_IfrsTitleOfIndividualAxis=glpg_CeoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	glpg_IfrsTitleOfIndividualAxis=glpg_MembersOfExecutiveCommitteeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Events after balance sheet date (Details)		12 Months Ended
Events after balance sheet date (Details)	Mar. 17, 2020 EUR (€) € / shares shares	Dec. 31, 2019 EquityInstruments	Dec. 31, 2018 EquityInstruments	Dec. 31, 2017 EquityInstruments
Disclosure of non-adjusting events after reporting period [line items]
Warrants exercised \| EquityInstruments		754,605	567,270	368,200
Exercise of Warrants [Member]
Disclosure of non-adjusting events after reporting period [line items]
Warrants exercised	152,220
Average exercise price warrants \| € / shares	€ 35.18
Increase to share capital and issuance premium due to warrants issued	€ 5,354,538.80
Number of shares issued \| shares	152,220
Closing share price \| € / shares	€ 141.40
CEO [member] \| Exercise of Warrants [Member]
Disclosure of non-adjusting events after reporting period [line items]
Warrants exercised	15,000
Members of Executive Committee [member] \| Exercise of Warrants [Member]
Disclosure of non-adjusting events after reporting period [line items]
Warrants exercised	15,000
Members of Board of Directors [member] \| Exercise of Warrants [Member]
Disclosure of non-adjusting events after reporting period [line items]
Warrants exercised	17,520