Pension And Other Postretirement Benefits (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Pension Benefits - U.S.
Service cost	$ 208	$ 203	$ 563	$ 616
Interest cost	192	179	574	540
Expected return on plan assets	(143)	(182)	(427)	(545)
Amortization of actuarial loss/(gain) and prior service cost	77	93	233	276
Net pension enhancement and curtailment/settlement cost	54	63	161	189
Net benefit cost	388	356	1,104	1,076
Pension Benefits - Non-U.S. [Member]
Service cost	136	149	413	461
Interest cost	189	185	573	571
Expected return on plan assets	(192)	(233)	(581)	(722)
Amortization of actuarial loss/(gain) and prior service cost	102	113	260	344
Net pension enhancement and curtailment/settlement cost				33
Net benefit cost	235	214	665	687
Other Postretirement Benefits [Member]
Service cost	38	40	104	111
Interest cost	79	75	237	226
Expected return on plan assets	(4)	(5)	(12)	(17)
Amortization of actuarial loss/(gain) and prior service cost	3	19	10	57
Net benefit cost	$ 116	$ 129	$ 339	$ 377