Accounting Principles - Going Concern (Details) - EUR (€) € in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounting Principles
Cash and cash equivalents	€ 86,553	€ 105,687	€ 35,840	€ 56,692
Short-term deposits	8,800
Research tax credits receivable from current tax year	4,400	€ 4,800
Milestone payments received	4,000
Maximum potential amount of sale of ordinary shares	€ 68,100

The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of short-term deposits held by the entity that are not classified as cash equivalents. [Refer: Cash equivalents]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References

No definition available.

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- Definition

Represents the cumulative amount of research funding received in a collaborative arrangement.

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No definition available.

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- Definition

Represents the maximum potential amount of sale of ordinary shares.

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- Definition

The amount of research tax credit receivables attributable to the current tax year, classified as current.

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No definition available.

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