Lease agreements - Lease liabilities (Details) - EUR (€) € in Millions	Dec. 31, 2019	Jan. 01, 2019
Presentation of leases for lessee [abstract]
Total lease liabilities	€ 6,492	€ 6,530
Non-current lease liabilities	5,225	5,239
Current lease liabilities	€ 1,267	€ 1,291

The amount of current lease liabilities. [Refer: Lease liabilities]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2019-01-01
-Paragraph 47
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2019-en-r&anchor=para_47_b&doctype=Standard
-URIDate 2019-03-27

+ Details

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

- Definition

The amount of liabilities related to the entity's leases. Lease is a contract, or part of a contract, that conveys the right to use an underlying asset for a period of time in exchange for consideration.

+ References

+ Details

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

- Definition

The amount of non-current lease liabilities. [Refer: Lease liabilities]

+ References

+ Details

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

- References

No definition available.

+ Details

Name:	ifrs-full_PresentationOfLeasesForLesseeAbstract
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration