Profit attributable to non-controlling interests (Details) - GBP (£) £ in Millions	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
(Loss)/profit attributable to non-controlling interests	£ (16)	£ 29
RFS Holdings BV Consortium Members
(Loss)/profit attributable to non-controlling interests	(17)	27
Other
(Loss)/profit attributable to non-controlling interests	£ 1	£ 2

The profit (loss) attributable to non-controlling interests. [Refer: Profit (loss); Non-controlling interests]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2017-01-01
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-Subparagraph e
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-URIDate 2017-03-09

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 81B
-Subparagraph a
-Clause i
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_81B_a_i&doctype=Standard
-URIDate 2017-03-09

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