FINANCE LEASE RECEIVABLES (Details) - GBP (£) £ in Millions	Dec. 31, 2019	Dec. 31, 2018
Disclosure of maturity analysis of finance lease payments receivable [text block] [Abstract]
Capital Leases, Net Investment in Direct Financing Leases, Allowance for Uncollectible Minimum Lease Payments	£ 12	£ 1

The estimate of contractual payments on direct financing leases that are probable of not being collected as of the balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=84165051&loc=d3e45377-112738

Name:	us-gaap_CapitalLeasesNetInvestmentInDirectFinancingLeasesAllowanceForUncollectibleMinimumLeasePayments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant