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Pensions and Other Post-employment Benefit Obligations - Summary of Amounts Recognized in the Consolidated Statement of Financial Position (Detail) - EUR (€) € in Millions	Dec. 31, 2018	Dec. 31, 2017
Disclosure of net defined benefit liability (asset) [line items]
Present value of funded obligation	€ 674	€ 691
Fair value of plan assets	(380)	(387)
Deficit of funded plans	294	304
Present value of unfunded obligation	316	360
Net liability arising from defined benefit obligation	610	664
Pension benefits [member]
Disclosure of net defined benefit liability (asset) [line items]
Present value of funded obligation	674	691
Fair value of plan assets	(380)	(387)
Deficit of funded plans	294	304
Present value of unfunded obligation	115	110
Net liability arising from defined benefit obligation	409	414
Other benefits [member]
Disclosure of net defined benefit liability (asset) [line items]
Present value of unfunded obligation	201	250
Net liability arising from defined benefit obligation	€ 201	€ 250

X

- Definition

Present value of unfunded obligation.

+ References

No definition available.

+ Details

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X

- Definition

The present value, without deducting any plan assets, of expected future payments required to settle the obligation resulting from employee service in the current and prior periods. [Refer: Plan assets, at fair value]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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 non-current net defined benefit liability. [Refer: Net defined benefit liability]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 55
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- Definition

The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2018-01-01
-Paragraph 57
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-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_57_a&doctype=Standard
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- Definition

The fair value of any plan assets, less the present value of the defined benefit obligation. [Refer: Plan assets [member]]

+ References

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