Purchases and other expenses - Prepaid expenses - Components (Details) - EUR (€) € in Millions	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Purchases and other expenses [abstract]
Prepaid external purchases	€ 678		€ 522	€ 408
Other prepaid operating expenses	52		49	47
Total	€ 730	€ 536	€ 571	€ 455	€ 394

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 2019-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2019-03-27

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