Other Financial Data - Schedule of Other Income (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other Financial Data [Abstract]
Equity earnings	$ 12	$ 20	$ 13
Gain on investments	4us-gaap_GainLossOnSaleOfInvestments	28us-gaap_GainLossOnSaleOfInvestments	7us-gaap_GainLossOnSaleOfInvestments
Gain on disposal of business	24	10	1
Foreign currency remeasurement gain (loss)	18	13	(19)
Derivative (loss) gain	(19)	(10)	3
Other	5us-gaap_OtherNonoperatingExpense	7us-gaap_OtherNonoperatingExpense	(3)us-gaap_OtherNonoperatingExpense
Other income	$ 44us-gaap_OtherNonoperatingIncomeExpense	$ 68us-gaap_OtherNonoperatingIncomeExpense	$ 2us-gaap_OtherNonoperatingIncomeExpense

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

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The gain (loss) resulting from the sale of a disposal group that is not a discontinued operation. It is included in income from continuing operations before income taxes in the income statement.

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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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