Santander Group - Acquisition of Deutsche Bank Polska (Details) - Retail and Private Banking Business of Deutsche Bank Polska SA - Goal € in Millions	Mar. 02, 2018 EUR (€)
Disclosure of detailed information about business combination [line items]
Proportion of ownership interest under purchase agreement	10.00%
Purchase price at acquisition date	€ 305

The fair value, at acquisition date, of the consideration transferred in a business combination. [Refer: Business combinations [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2017-01-01
-Paragraph B64
-Subparagraph f
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=3&date=2017-03-01&anchor=para_B64_f&doctype=Appendix&seq=2
-URIDate 2017-03-09

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