Related party disclosures - Summary of Related Party Disclosures for Associates and Joint Ventures (Detail) - Associates [member] - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disclosure of transactions between related parties [Line Items]
Fee revenue from associates	$ 3	$ 1	$ 10
Amounts owed by associates	11	11	3
Amounts owed to associates	$ 0	$ (4)	$ (4)

The amounts payable resulting from related party transactions. [Refer: Related parties [member]]

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- Definition

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.

+ References

No definition available.

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- Definition

The amount of revenue arising from the rendering of services in related party transactions. [Refer: Revenue; Related parties [member]]

+ References

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- Definition

The amount of receivables due from related parties. [Refer: Related parties [member]]

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