Pensions and other post-employment benefits - Present value (Details) - EUR (€) € in Millions	Dec. 31, 2017	Dec. 31, 2016
Wholly funded
Net defined benefit
Present value of obligations	€ 18,940	€ 21,271
Partly funded
Net defined benefit
Present value of obligations	5,248	6,122
Unfunded
Net defined benefit
Present value of obligations	€ 1,310	€ 1,270

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]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2017-01-01
-Paragraph 57
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_57_a&doctype=Standard
-URIDate 2017-03-09

Name:	ifrs-full_DefinedBenefitObligationAtPresentValue
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant