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, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, beginning	$ 1,736
Fair value of plan assets, ending	2,018	$ 1,736
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation, beginning	2,323	3,109
Service cost	58	66	$ 78
Interest cost	82	93	106
Actuarial loss (gain)	363	(278)
Employee contributions	2	2
Curtailments	0	(1)
Settlements	35	(528)
Defined Benefit Plan, Benefit Obligation, Business Combination	26	0
Benefits paid	(249)	(99)
Plan Amendments	(2)	2
Foreign currency effects	12	(43)
Benefit obligation, ending	2,650	2,323	3,109
Fair value of plan assets, beginning	1,736	2,448
Actual return on plan assets	348	(122)
Employer contributions	166	66
Employee contributions	2	2
Settlements	(10)	(528)
Defined Benefit Plan, Plan Assets, Business Combination	7	0
Benefits Paid	(249)	(99)
Foreign currency effects	18	(31)
Fair value of plan assets, ending	2,018	1,736	2,448
Funded status	(632)	(587)
Prepaid benefit cost	38	53
Accrued benefit liability - current	(18)	(17)
Accrued benefit liability - long-term	(652)	(623)
Net amount recognized in the balance sheet	(632)	(587)
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation, beginning	144	154
Service cost	2	2	2
Interest cost	5	5	6
Actuarial loss (gain)	24	(4)
Curtailments	0	0
Settlements	3
Defined Benefit Plan, Benefit Obligation, Business Combination	3
Benefits paid	(14)	(13)
Plan Amendments	0	0
Foreign currency effects	0	0
Benefit obligation, ending	167	144	$ 154
Fair value of plan assets, beginning	0
Employer contributions	14	13
Defined Benefit Plan, Plan Assets, Business Combination	0	0
Benefits Paid	(14)	(13)
Fair value of plan assets, ending	0	0
Funded status	(167)	(144)
Accrued benefit liability - current	(16)	(13)
Accrued benefit liability - long-term	(151)	(131)
Net amount recognized in the balance sheet	$ (167)	$ (144)