Other Financial Data - Schedule of Other Income (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Other (Expense) Income
Foreign currency remeasurement gain	$ 24	$ 19
Gain on disposal of business	19	0
Equity earnings	2	5
Loss on investments	(2)us-gaap_GainLossOnSaleOfInvestments	(1)us-gaap_GainLossOnSaleOfInvestments
Derivative loss	(1)	(23)
Other	0us-gaap_OtherNonoperatingExpense	1us-gaap_OtherNonoperatingExpense
Total	$ 42us-gaap_OtherNonoperatingIncomeExpense	$ 1us-gaap_OtherNonoperatingIncomeExpense

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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The aggregate amount of other expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating expense recognized during the period. Such amounts may include: (a) unusual costs, (b) loss on foreign exchange transactions, (c) losses on securities (net of profits), and (d) miscellaneous other expense items.

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The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

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