Pension Benefit Plans (Components Of Net Periodic Pension Costs) (Details) - Pension benefit plans - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ (40)	$ (31)	$ (32)
Total	(21)	(16)	$ 5
U.S. Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	(6)
Interest cost	(69)	(89)
Expected return on plan assets	121	126
Amortization of prior service credit	(1)	(1)
Amortization of net loss	(37)	(26)
Curtailment and settlement gains (losses) recognized	0	0
Total	14	4
Non-U.S. Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	(40)	(25)
Interest cost	(22)	(24)
Expected return on plan assets	37	40
Amortization of prior service credit	1	0
Amortization of net loss	(10)	(4)
Curtailment and settlement gains (losses) recognized	(1)	(7)
Total	$ (35)	$ (20)