Employee Information - Summary of Classification of Employee Benefit (Detail) - GBP (£) £ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Employee benefit expense
Wages and salaries (including termination costs)	£ 1,382	£ 1,180	£ 1,152
Social security costs	113	95	96
Share-based payment costs	35	28	29
Retirement benefits - defined contribution plans	46	37	47
Retirement benefits - defined benefit plans	29	25	13
Total	£ 1,605	£ 1,365	£ 1,337

The expense of all forms of consideration given by an entity in exchange for a service rendered by employees or for the termination of employment.

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The amount of expense from share-based payment transactions with employees. [Refer: Expense from share-based payment transactions]

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The amount of post-employment benefit expense included in profit or loss relating to defined benefit plans. [Refer: Profit (loss); Defined benefit plans [member]] [Contrast: Increase (decrease) in net defined benefit liability (asset) resulting from expense (income) in profit or loss]

+ References

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The amount of post-employment benefit expense relating to defined contribution plans. Defined contribution plans are post-employment benefit plans under which an entity pays fixed contributions into a separate entity (a fund) and will have no legal or constructive obligation to pay further contributions if the fund does not hold sufficient assets to pay all employee benefits relating to employee service in the current and prior periods.

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A class of employee benefits expense that represents social security contributions. [Refer: Employee benefits expense]

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A class of employee benefits expense that represents wages and salaries. [Refer: Employee benefits expense]

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