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Deferred tax assets and liabilities - Net deferred tax balance (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | ---
Income Taxes [Abstract] |  |  |
Offsetting amounts | $ 627 | $ 578 |
Deferred tax assets | 399 | 354 |
Deferred tax liabilities | (1,196) | (1,386) |
Net deferred tax balance | $ (797) | $ (1,032) | $ (858)

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- Definition Deferred Tax Liability (Asset), Offsetting Amounts + References No definition available. + Details
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- Definition Income Taxes [Abstract] + References No definition available. + Details
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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 + Details
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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 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 + Details
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