Related party disclosures - Summary of Related Party Disclosures for Associates and Joint Ventures (Detail) - Associates [member] - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Disclosure of transactions between related parties [Line Items]
Fee revenue	$ 9	$ 3	$ 1
Amounts receivable	$ 10	11	11
Amounts payable		$ 0	$ (4)

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 24
-IssueDate 2022-03-24
-Paragraph 20
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-URIDate 2022-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-IssueDate 2022-03-24
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-Subparagraph b
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-URIDate 2022-03-24

+ Details

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Balance Type:	credit
Period Type:	instant

- 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.

+ Details

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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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-Name IAS
-Number 24
-IssueDate 2022-03-24
-Paragraph 21
-Subparagraph c
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- Definition

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

+ References

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-Name IAS
-Number 1
-IssueDate 2022-03-24
-Paragraph 78
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2022-en-r&anchor=para_78_b&doctype=Standard
-URIDate 2022-03-24

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