CONSOLIDATED STATEMENT OF CHANGES IN EQUITY (Parenthetical) - GBP (£) £ in Millions	6 Months Ended
Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020
CONSOLIDATED STATEMENT OF CHANGES IN EQUITY [Abstract]
Total comprehensive income attributable to owners of the parent	£ 3,046	£ 601	£ 827
Equity attributable to owners of parent	£ 51,667	£ 49,184	£ 48,640

The amount of comprehensive income attributable to owners of the parent. [Refer: Comprehensive income]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration