Investments (Schedule Of Investments) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Investments [Abstract]
Time deposits	$ 913us-gaap_OtherShortTermInvestments		$ 1,295us-gaap_OtherShortTermInvestments
Pledged money market funds	38		38
Available-for-sale investments	9us-gaap_AvailableForSaleSecurities		7us-gaap_AvailableForSaleSecurities
Equity method investments	1,111us-gaap_EquityMethodInvestments		1,114us-gaap_EquityMethodInvestments
Restricted cash	26us-gaap_OtherRestrictedAssetsCurrent		26us-gaap_OtherRestrictedAssetsCurrent
Other investments	33us-gaap_OtherInvestments		33us-gaap_OtherInvestments
Total	2,130us-gaap_Investments		2,513us-gaap_Investments
Dividends received	$ 79	$ 59

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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This item represents disclosure of the amount of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporation; these investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Sum of the carrying amounts as of the balance sheet date of all investments.

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Other investments not otherwise specified in the taxonomy.

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Other short-term assets not otherwise listed in the existing taxonomy that are pledged or subject to withdrawal restrictions.

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Other investments not otherwise specified in the taxonomy that will be realized in a short period of time, usually less than one year or the normal operating cycle, whichever is longer.

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The carrying amount as of the date of the latest financial statement presented of securities which are owned but transferred to serve as collateral for letter of credit arrangements, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party.

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