OTHER RESERVES (Details) - Share buy-back programme [member] - GBP (£) £ in Millions, shares in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
OTHER RESERVES (Details) [Line Items]
Stock Repurchased and Retired During Period, Shares (in Shares)	1,887	1,578
Stock Repurchased and Retired During Period, Value	£ 1,095	£ 1,005
Capital redemption reserve [member]
OTHER RESERVES (Details) [Line Items]
Credit derivative, nominal amount	£ 189	£ 158

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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