Income Taxes (Significant Components Of Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current
Federal	$ 541	$ 327	$ 270
State	53	5	17
Foreign	127	146	158
Deferred
Federal	(645)	18	17
State	(6)	28	9
Foreign	(63)	10	(33)
Total Income Taxes	$ 7	$ 534	$ 438