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Trade Receivables and Other - Summary of Carrying Amounts of Total Trade Receivables - Net by Currency (Detail) - EUR (€) € in Millions	Jun. 30, 2018	Dec. 31, 2017
Trade receivables [line items]
Total trade receivables-net	€ 526	€ 306
Euro [member]
Trade receivables [line items]
Total trade receivables-net	267	124
U.S. Dollar [member]
Trade receivables [line items]
Total trade receivables-net	232	164
Swiss Franc [member]
Trade receivables [line items]
Total trade receivables-net	8	4
Other currencies [member]
Trade receivables [line items]
Total trade receivables-net	€ 19	€ 14

X

- Definition

Trade receivables [line items]

+ References

No definition available.

+ Details

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X

- Definition

The amount due from customers for goods and services sold.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
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-IssueDate 2017-01-01
-Paragraph 78
-Subparagraph b
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-URIDate 2017-03-09

+ Details

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Balance Type:	debit
Period Type:	instant

X

- Details

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- Details

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- Details

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Period Type:

X

- Details

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