Investments (Schedule Of Investments) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Investments Schedule [Abstract]
Equity method investments	$ 1,048	$ 1,214
Time deposits	255	613
Available for sale debt instruments	491	490
Equity and other investments	44	48
Restricted Cash and Cash Equivalents	176	74	$ 68
Total	2,014	2,439
Equity Method Investments and Joint Ventures [Abstract]
Dividends received from equity method investments	325	$ 247
Undistributed earnings from equity method investments	$ 104

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