Warrant plans - Category (Details)	12 Months Ended
Dec. 31, 2019 EquityInstruments € / shares	Dec. 31, 2018 EquityInstruments € / shares	Dec. 31, 2017 EquityInstruments € / shares	Dec. 31, 2016 EquityInstruments € / shares
Warrant Plans
Total warrants outstanding	5,541,117	4,626,782	3,970,807	3,466,407
Exercise Price \| € / shares	€ 70.09	€ 53.30	€ 39.32	€ 27.1
Weighted average remaining expected life	1439 days	1500 days	1441 days
Non-executive directors
Warrant Plans
Total warrants outstanding	222,600	216,780	216,060
Executive team
Warrant Plans
Total warrants outstanding	2,171,874	2,139,374	2,039,374
Other
Warrant Plans
Total warrants outstanding	3,146,643	2,270,628	1,715,373

The weighted average remaining contractual life of outstanding of other equity instruments.

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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.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 2
-IssueDate 2019-01-01
-Paragraph 45
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_45&doctype=Standard
-URIDate 2019-03-27

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- Definition

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

+ References

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