Income Taxes - Summary of the Balances of the Deferred tax Assets and Liabilities in Statement of Financial Position (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Disclosure of Deferred Tax Assets And Liabilities [line items]
Asset	$ 740	$ 627
Liability	(658)	(720)
Net	82	(93)
Country of domicile [member]
Disclosure of Deferred Tax Assets And Liabilities [line items]
Asset	152	189
Liability	(229)	(346)
Net	(77)	(157)
Foreign countries [member]
Disclosure of Deferred Tax Assets And Liabilities [line items]
Asset	588	438
Liability	(429)	(374)
Net	$ 159	$ 64

Disclosure of Deferred Tax Assets And Liabilities [line items]

No definition available.

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- Definition

The amount of deferred tax liabilities or assets. [Refer: Deferred tax liabilities; Deferred tax assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2020-01-01
-Paragraph 81
-Subparagraph g
-Clause i
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2020-en-r&anchor=para_81_g_i&doctype=Standard
-URIDate 2020-01-01

+ Details

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- Definition

The amount of deferred tax assets net of deferred tax liabilities, when the absolute amount of deferred tax assets is greater than the absolute amount of deferred tax liabilities. [Refer: Deferred tax assets; Deferred tax liabilities]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 12
-IssueDate 2020-01-01
-Paragraph 81
-Subparagraph g
-Clause i
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=12&code=ifrs-tx-2020-en-r&anchor=para_81_g_i&doctype=Standard
-URIDate 2020-01-01

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- Definition

The amount of deferred tax liabilities net of deferred tax assets, when the absolute amount of deferred tax liabilities is greater than the absolute amount of deferred tax assets. [Refer: Deferred tax assets; Deferred tax liabilities]

+ References

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