Equity - Capital (Details) - EUR (€) € in Millions	Jun. 30, 2020	Dec. 31, 2019
Equity [abstract]
Number of shares outstanding (in shares)	16,618,114,582	16,618,114,582
Notional amount	€ 8,309	€ 8,309

The number of shares that have been authorised and issued, reduced by treasury shares held. [Refer: Treasury shares]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 79
-Subparagraph a
-Clause iv
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_79_a_iv&doctype=Standard
-URIDate 2019-03-27

Name:	ifrs-full_NumberOfSharesOutstanding
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant