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Provisions - Summary of Legal Claims and Other Costs (Detail) - EUR (€) € in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure of other provisions [line items]
Total provisions for legal claims and other costs	€ 153	€ 149	€ 163
Legal claims and other costs [member]
Disclosure of other provisions [line items]
Maintenance and customer related provisions	25	14
Litigation	36	35
Disease claims	3	4
Other	3	3
Total provisions for legal claims and other costs	€ 67	€ 56	€ 67

X

- Definition

Maintenance and customer related provisions.

+ References

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- Definition

Provision for disease claims.

+ References

No definition available.

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X

- Definition

Provision for litigation.

+ References

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.

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- Definition

The amount of miscellaneous other provisions. [Refer: Other provisions]

+ References

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

The amount of provisions other than provisions for employee benefits. [Refer: Provisions]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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