Provisions - Sensitivity of the Value of Termination, Post-Employment and Other Obligations (Details) - Discount rate € in Millions	Dec. 31, 2017 EUR (€)
Decrease in actuarial assumption
Percent of possible decrease in actuarial assumption	(1.00%)
Impact on value	€ (270)
Impact on income statement	€ (230)
Increase in actuarial assumption
Percentage of possible increase in actuarial assumption	1.00%
Impact on value	€ 248
Impact on income statement	€ 213

The increase (decrease) in a defined benefit obligation that would have been caused by a decrease in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2017-01-01
-Paragraph 145
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_145_a&doctype=Standard
-URIDate 2017-03-09

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- Definition

The increase (decrease) in a defined benefit obligation that would have been caused by an increase in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [member]]

+ References

+ Details

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- Definition

The reasonably possible percentage of the decrease in the actuarial assumption used to determine the present value of defined benefit obligation. [Refer: Actuarial assumptions [member]]

+ References

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- Definition

The reasonably possible percentage of the increase in the actuarial assumption used to determine the present value of defined benefit obligation. [Refer: Actuarial assumptions [member]]

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- Definition

Decrease In Actuarial Assumption [Abstract]

+ References

No definition available.

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- Definition

Decrease In Income Due To Reasonably Possible Increase In Actuarial Assumption

+ References

No definition available.

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- Definition

Increase In Actuarial Assumption [Abstract]

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No definition available.

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- Definition

Increase In Income Due To Reasonably Possible Decrease In Actuarial Assumption

+ References

No definition available.

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