Risks Arising from Financial Instruments - Summary of Foreign Exchange Results Recognized on Unhedged and Hedged Exposures (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net foreign exchange results [line items]
Net foreign exchange	$ (84)	$ 14	$ (180)
Economic Hedges [Member]
Net foreign exchange results [line items]
Net foreign exchange	717	(181)	6
Other Results - Not Hedged [Member]
Net foreign exchange results [line items]
Net foreign exchange	$ (801)	$ 195	$ (186)

The fair value of financial instruments designated as hedging instruments. Hedging instruments are designated derivatives or (for a hedge of the risk of changes in foreign currency exchange rates only) designated non-derivative financial assets or non-derivative financial liabilities whose fair value or cash flows are expected to offset changes in the fair value or cash flows of a designated hedged item. [Refer: At fair value [member]; Derivatives [member]; Derivative financial assets; Derivative financial liabilities; Financial instruments, class [member]; Financial assets; Financial liabilities]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2023-01-01
-Name IFRS
-Number 7
-IssueDate 2021-01-01
-Paragraph 22
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_22_b&doctype=Standard&book=b
-URIDate 2021-03-24

Name:	ifrs-full_FinancialInstrumentsDesignatedAsHedgingInstrumentsAtFairValue
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant