Investments in associates and joint ventures - Disclosure of investments in associates and joint ventures (Details) - GBP (£) £ in Millions	Dec. 31, 2023	Dec. 31, 2022
Investments in subsidiaries, joint ventures and associates reported in separate financial statements [abstract]
Investments in associates accounted for using equity method	£ 670	£ 695
Held at fair value through profit or loss, Associates	0	0
Associates	670	695
Investments in joint ventures accounted for using equity method	209	227
Held at fair value through profit or loss, Joint ventures	516	435
Joint ventures	725	662
Equity accounted	879	922
Held at fair value through profit or loss	516	435
Total	£ 1,395	£ 1,357

No definition available.

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- Definition

The fair value of investments in joint ventures if there are quoted market prices for the investment. [Refer: Joint ventures [member]; Investments in joint ventures reported in separate financial statements]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2023-01-01
-Paragraph 21
-Subparagraph b
-Clause iii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2023-en-r&anchor=para_21_b_iii&doctype=Standard
-URIDate 2023-03-23

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- Definition

The fair value of investments in associates if there are quoted market prices for the investment. [Refer: Associates [member]; Investments in associates reported in separate financial statements]

+ References

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- Definition

The amount of investments accounted for using the equity method. The equity method is a method of accounting whereby the investment is initially recognised at cost and adjusted thereafter for the post-acquisition change in the investor's share of net assets of the investee. The investor's profit or loss includes its share of the profit or loss of the investee. The investor's other comprehensive income includes its share of the other comprehensive income of the investee. [Refer: At cost [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2023-01-01
-Paragraph 24
-Subparagraph a
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2023-01-01
-Paragraph B16
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2023-en-r&anchor=para_B16&doctype=Appendix&subtype=B
-URIDate 2023-03-23

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2023-01-01
-Paragraph 54
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- Definition

The amount of investments in associates in an entity's separate financial statements. [Refer: Associates [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 27
-IssueDate 2023-01-01
-Paragraph 10
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=27&code=ifrs-tx-2023-en-r&anchor=para_10&doctype=Standard
-URIDate 2023-03-23

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The amount of investments in associates accounted for using the equity method. [Refer: Associates [member]; Investments accounted for using equity method]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The amount of investments in joint ventures in an entity's separate financial statements. [Refer: Joint ventures [member]]

+ References

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The amount of investments in joint ventures accounted for using the equity method. [Refer: Joint ventures [member]; Investments accounted for using equity method]

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The amount of investments in subsidiaries, joint ventures and associates in an entity's separate financial statements. [Refer: Associates [member]; Joint ventures [member]; Subsidiaries [member]; Investments in subsidiaries reported in separate financial statements]

+ References

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No definition available.

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