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Share-based payments - Summary of Employee Related Share Based Compensation Expense (Detail) - EUR (€) € in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure Of Detailed Information About Share Based Compensation Expense [Line Items] |  |  |
Share-based compensation expense | € 25,519 | € 2,016 | € 338
Research And Development Expense [Member] |  |  |
Disclosure Of Detailed Information About Share Based Compensation Expense [Line Items] |  |  |
Share-based compensation expense | 14,546 | 1,556 | 238
General And Administrative Expense [Member] |  |  |
Disclosure Of Detailed Information About Share Based Compensation Expense [Line Items] |  |  |
Share-based compensation expense | € 10,973 | € 460 | € 100

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- Definition The amount of expense from share-based payment transactions with employees. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_112_c&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition Disclosure of detailed information about share based compensation expense [Line Items]. + References No definition available. + Details
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- Details
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- Details
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