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Income taxes - Deferred income tax assets and liabilities (Details) (USD $)
In Millions, unless otherwise specified |
Dec. 31, 2014
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Dec. 31, 2013
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| Income Tax Disclosure [Abstract] | ||
| Current deferred income tax assets | $ 347us-gaap_DeferredTaxAssetsGrossCurrent | $ 393us-gaap_DeferredTaxAssetsGrossCurrent |
| Noncurrent deferred income tax assets | 172us-gaap_DeferredTaxAssetsGrossNoncurrent | 207us-gaap_DeferredTaxAssetsGrossNoncurrent |
| Current deferred income tax liabilities | (4)us-gaap_DeferredTaxLiabilitiesGrossCurrent | (1)us-gaap_DeferredTaxLiabilitiesGrossCurrent |
| Noncurrent deferred income tax liabilities | (399)us-gaap_DeferredTaxLiabilitiesGrossNoncurrent | (548)us-gaap_DeferredTaxLiabilitiesGrossNoncurrent |
| Net deferred income tax asset | $ 116us-gaap_DeferredTaxAssetsLiabilitiesNet | $ 51us-gaap_DeferredTaxAssetsLiabilitiesNet |
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- Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards expected to be realized or consumed within one year or operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards expected to be realized or consumed after one year (or the normal operating cycle, if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of deferred tax liability attributable to taxable temporary differences expected to be realized or consumed within one year or operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Gross amount of noncurrent deferred tax liabilities, which result from applying the applicable tax rate to taxable temporary differences pertaining to each jurisdiction to which the entity is obligated to pay income tax. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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