Share-based payments - Share based payments (Details) - GBP (£) £ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Disclosure of terms and conditions of share-based payment arrangement [line items]
Total equity settled	£ 423	£ 394	£ 349
Cash settled	3	4	2
Total share based payments	426	398	351
Deferred Share Value Plan / Share Value Plan
Disclosure of terms and conditions of share-based payment arrangement [line items]
Total equity settled	270	235	220
Others
Disclosure of terms and conditions of share-based payment arrangement [line items]
Total equity settled	£ 153	£ 159	£ 129

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

No definition available.

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- Definition

The amount of expense arising from cash-settled share-based payment transactions in which the goods or services received did not qualify for recognition as assets. [Refer: Expense from share-based payment transactions]

+ References

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

The amount of expense arising from equity-settled share-based payment transactions in which the goods or services received did not qualify for recognition as assets. [Refer: Expense from share-based payment transactions]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of expense arising from share-based payment transactions in which the goods or services received did not qualify for recognition as assets.

+ References

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