Consolidated Statement of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net income	$ 306us-gaap_NetIncomeLoss	$ 312us-gaap_NetIncomeLoss
Other comprehensive income/(loss), net of tax (Note 10)
Foreign currency translation	(482)	(82)
Other comprehensive income/(loss), net of tax	(482)	(82)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	(176)	230
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	1	0
Comprehensive income	$ (177)us-gaap_ComprehensiveIncomeNetOfTax	$ 230us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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