Disposals and other non-operating items - Summary of disposals and other non-operating item (Detail) - GBP (£) £ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disposals and other non-operating items
Revaluation of investments	£ (11)	£ 9	£ 16
Gain/(loss) on disposal of businesses and assets held for sale	(61)	(18)	39
Net gain/(loss) on disposals and other non-operating items	£ (72)	£ (9)	£ 55

The gains (losses) on financial assets at fair value through profit or loss. [Refer: Financial assets at fair value through profit or loss]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2023-01-01
-Paragraph 20
-Subparagraph a
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2023-en-r&anchor=para_20_a_i&doctype=Standard
-URIDate 2023-03-23

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Balance Type:	credit
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