Note 36 - Related Party Transactions - Transactions with Subsidiaries, Joint Ventures and Associates - Deposits (Detail) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Deposits (Transactions with Subsidiaries, Joint Ventures and Associates)
Deposits outstanding, beginning of year	€ 31	€ 63
Movement in deposits during the period	2	(32)
Changes in the group of consolidated companies	0	0
Exchange rate changes/other	0	0
Deposits outstanding, end of year	€ 33	€ 31

The amounts payable resulting from related party transactions. [Refer: Related parties [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 24
-IssueDate 2023-01-01
-Paragraph 20
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=24&code=ifrs-tx-2023-en-r&anchor=para_20&doctype=Standard
-URIDate 2023-03-23

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 24
-IssueDate 2023-01-01
-Paragraph 18
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=24&code=ifrs-tx-2023-en-r&anchor=para_18_b&doctype=Standard
-URIDate 2023-03-23

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