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Other Gains / (Losses)-Net - Summary of Other Gains/(Losses) Net (Detail) - EUR (€) € in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Analysis of income and expense [abstract]
Realized (losses) / gains on derivatives	€ (14)	€ 15	€ (28)	€ 22
Unrealized (losses) / gains on derivatives at fair value through profit and loss - net	(14)	11	17	(43)
Unrealized exchange (losses) / gains from the remeasurement of monetary assets and liabilities - net	(1)			1
Losses on disposal	(1)	(3)	(2)	(4)
Other		1	(1)	1
Total other gains / (losses) - net	€ (30)	€ 24	€ (14)	€ (23)

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- Definition

Miscellaneous other gains (losses)

+ References

No definition available.

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- Definition

Realized gain (losses) on derivatives.

+ References

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- Definition

Unrealized exchange gains / (losses) from the remeasurement of monetary assets and liabilities, net.

+ References

No definition available.

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- Definition

Unrealized gains (losses) on change in fair value of derivatives.

+ References

No definition available.

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- Definition

The gains (losses) on disposals of non-current assets. [Refer: Non-current assets]

+ References

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

The gains (losses) that the entity does not separately disclose in the same statement or note.

+ References

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