Income Taxes (Details 4) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Deferred tax assets:
Allowance for credit losses	$ 149	$ 144	$ 159
Net operating loss carryforwards	46	56	59
Deferred tax assets, gross	195us-gaap_DeferredTaxAssetsGross	200us-gaap_DeferredTaxAssetsGross	218us-gaap_DeferredTaxAssetsGross
Deferred tax liabilities
Deferred income tax liabilities (primarily lease basis differences)	(514)	(455)	(467)
Valuation allowance for deferred income tax assets	(3)	(9)	(9)
Deferred income tax on translation adjustment	(252)	(133)	(173)
Deferred income taxes, net	$ (574)us-gaap_DeferredTaxAssetsLiabilitiesNet	$ (397)us-gaap_DeferredTaxAssetsLiabilitiesNet	$ (431)us-gaap_DeferredTaxAssetsLiabilitiesNet

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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