Provisions - Individual Suspension Plan (Details) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Disclosure of defined benefit plans [line items]
Provisions for employee benefits	€ 6,578	€ 7,149
Individual Suspension Plan
Disclosure of defined benefit plans [line items]
Provisions for employee benefits	€ 3,580	€ 3,666
Discount rate	1.05%
Average duration of plans	5 years 2 months 12 days

The discount rate used as the significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [member]]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-IssueDate 2017-01-01
-Paragraph 144
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_144&doctype=Standard
-URIDate 2017-03-09

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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 amount of provisions for employee benefits. [Refer: Employee benefits expense; Provisions]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 78
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_78_d&doctype=Standard
-URIDate 2017-03-09

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- Definition

Weighted Average Duration Of Plan

+ References

No definition available.

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