Investments (Schedule Of Investments) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Investments Schedule [Abstract]
Equity method investments	$ 1,242	$ 1,230
Time deposits	665	456
Available-for-sale investments	537	244
Other investments	33	35
Restricted Cash and Cash Equivalents	68	69
Total	2,545	2,034
Equity Method Investments and Joint Ventures [Abstract]
Dividends received from equity method investments	314	$ 239
Undistributed earnings from equity method investments	$ 292

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

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

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Amount of short-term investments classified as other.

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

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Amount of consolidated retained earnings that represent undistributed (not yet received) earnings from 50% or less owned persons accounted for by the equity method (equity method investees).

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