Income taxes - Deferred tax assets and liabilities (Details) - USD ($) $ in Millions |
Dec. 31, 2020 |
Dec. 31, 2019 |
|---|---|---|
| Income Tax Disclosure [Abstract] | ||
| Deferred tax assets | $ 343 | $ 197 |
| Deferred tax liabilities | (90) | (78) |
| Net deferred tax asset | $ 253 | $ 119 |
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- Definition Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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