Fair Value - Effect of Changes in Significant Unobservable Assumptions to Reasonably Possible Alternatives (Detail) - EUR (€)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Fair Value Financial Assets And Liabilities [abstract]
Increase (decrease) in fair value measurement due to change in one or more unobservable inputs to reflect reasonably possible alternative assumptions, liabilities	€ 2,484	€ 1,831
Increase in fair value measurement due to change in one or more unobservable inputs to reflect reasonably possible alternative assumptions, liabilities	131	125
Decrease in fair value measurement due to change in one or more unobservable inputs to reflect reasonably possible alternative assumptions, liabilities	€ (126)	€ (120)

Disclosure Of Fair Value Financial Assets And Liabilities [abstract]

No definition available.

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- Definition

The amount of decrease in the fair value measurement of liabilities due to a change in one or more unobservable inputs to reflect reasonably possible alternative assumptions.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 13
-IssueDate 2018-01-01
-Paragraph 93
-Subparagraph h
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2018-03-01&anchor=para_93_h_ii&doctype=Standard
-URIDate 2018-03-16

+ Details

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- Definition

The amount of increase (decrease) in the fair value measurement of liabilities due to a change in one or more unobservable inputs to reflect reasonably possible alternative assumptions.

+ References

+ Details

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- Definition

The amount of increase in the fair value measurement of liabilities due to a change in one or more unobservable inputs to reflect reasonably possible alternative assumptions.

+ References

+ Details

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