Other assets - Text details (Detail) - EUR (€) € in Millions	Dec. 31, 2017	Dec. 31, 2016
Current assets [Member]
Other assets [Line items]
Prepaid expenses	€ 206	€ 258
Accrued income	186	228
Non-current assets [member]
Other assets [Line items]
Non-current prepaid expenses	€ 74	€ 90

The amount recognised as a current asset for expenditures made prior to the period when the economic benefit will be realised.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_112_c&doctype=Standard
-URIDate 2017-03-09

Name:	ifrs-full_CurrentPrepaidExpenses
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant