Staff costs and Directors' remuneration - Summary of Staff Costs (Parenthetical) (Detail) $ in Millions	12 Months Ended
Dec. 31, 2023 USD ($)
Exceptional items [member] \| Reorganisation programmes [member]
Disclosure of information about employees and directors [Line Items]
Exceptional items	$ 1

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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