Warrant Plans - Category (Details)	12 Months Ended
Dec. 31, 2017 EUR (€) EquityInstruments	Dec. 31, 2016 EUR (€) EquityInstruments	Dec. 31, 2015 EUR (€) EquityInstruments	Dec. 31, 2014 EUR (€) EquityInstruments
Warrant Plans
Total warrants outstanding	3,970,807	3,466,407	2,805,692	3,590,853
Exercise Price \| €	€ 39.32	€ 27.06	€ 16.22	€ 12.1
Weighted average remaining expected life	1441 days	1482 days	1469 days
Non-executive directors
Warrant Plans
Total warrants outstanding	216,060	165,240	115,730
Executive team
Warrant Plans
Total warrants outstanding	2,039,374	1,676,874	1,376,874
Other
Warrant Plans
Total warrants outstanding	1,715,373	1,624,293	1,313,088

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

No definition available.

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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 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 2017-01-01
-Paragraph 45
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_45&doctype=Standard
-URIDate 2017-03-09

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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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