Impairment of Non-current Assets - Summary of Goodwill Alloctaed to Cash Generating Units (Parenthetical) (Detail) - USD ($) $ in Millions	Jun. 30, 2021	Jun. 30, 2020
Disclosure of detailed information about goodwill allocated to cash generating unit explanatory [line items]
Goodwill	$ 1,197	$ 1,197
Increase (Decrease) Due To Changes in Accounting Policy Required By IFRS [Member] \| IAS 12 [Member]
Disclosure of detailed information about goodwill allocated to cash generating unit explanatory [line items]
Goodwill		$ 950

The amount of assets representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognised. [Refer: Business combinations [member]]

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant