Pension schemes - Summary of net pension obligations and net pension assets (Details) - GBP (£) £ in Millions	Dec. 31, 2023	Dec. 31, 2022
Pension schemes
Net pension assets	£ 119	£ 129
Net pension obligation	(182)	(184)
Overall net pension balance	£ (63)	£ (55)

No definition available.

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- Definition

The amount of deficit or surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2023-01-01
-Paragraph 140
-Subparagraph a
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-URIDate 2023-03-23

+ Details

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- Definition

The amount of non-current net defined benefit asset. [Refer: Net defined benefit asset]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2023-01-01
-Paragraph 55
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_55&doctype=Standard
-URIDate 2023-03-23

+ Details

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- Definition

The amount of non-current net defined benefit liability. [Refer: Net defined benefit liability]

+ References

+ Details

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