Employee Benefit Plans (Changes In Defined Benefit Obligation And Fair Value Of Defined Benefit Plan Assets) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, beginning	$ 1,922
Fair value of plan assets, ending	2,131	$ 1,922
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation, beginning	2,880	3,305
Service cost	82	92	$ 71
Interest cost	113	112	126
Actuarial loss (gain)	132	(117)
Employee contributions	1	2
Curtailments	0	(2)
Settlements	(10)	(323)
Divestitures	(8)	(1)
Benefits paid	(142)	(91)
Plan Amendments	0	(1)
Actual expenses	(2)	(2)
Foreign currency effects	(54)	(94)
Benefit obligation, ending	2,992	2,880	3,305
Fair value of plan assets, beginning	1,922	2,194
Actual return on plan assets	232	(7)
Employer contributions	183	222
Employee contributions	1	2
Settlements	(10)	(328)
Divestitures	(2)	(1)
Benefits paid	(142)	(91)
Actual Expenses	(2)	(2)
Foreign currency effects	(51)	(67)
Fair value of plan assets, ending	2,131	1,922	2,194
Funded status	(861)	(958)
Prepaid benefit cost	30	32
Accrued benefit liability - current	(16)	(16)
Accrued benefit liability - long-term	(875)	(974)
Net amount recognized in the balance sheet	(861)	(958)
Other Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation, beginning	199	231
Service cost	3	5	4
Interest cost	8	8	8
Actuarial loss (gain)	5	(32)
Curtailments	(38)
Settlements	0
Divestitures	0	(1)
Benefits paid	(9)	(11)
Plan Amendments	3	0
Foreign currency effects	0	(1)
Benefit obligation, ending	171	199	$ 231
Employer contributions	9	11
Benefits paid	(9)	(11)
Funded status	(171)	(199)
Accrued benefit liability - current	(13)	(13)
Accrued benefit liability - long-term	(158)	(186)
Net amount recognized in the balance sheet	$ (171)	$ (199)