Retained profits - Narrative (Details) - Retained profits £m - GBP (£) £ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
RETAINED PROFITS (Details) - Narrative [Line Items]
Treasury and other bills	£ 10	£ 196	£ 205
Treasury shares held (in shares)	£ 61	£ 688	£ 434

An entity’s own equity instruments, held by the entity or other members of the consolidated group.

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