Pension And Other Postretirement Benefits (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Pension Benefits - U.S.
Service cost	$ 245	$ 208	$ 712	$ 563
Interest cost	177	192	531	574
Expected return on plan assets	(178)	(143)	(528)	(427)
Amortization of actuarial loss/(gain) and prior service cost	79	77	237	233
Net pension enhancement and curtailment/settlement cost	52	54	156	161
Net benefit cost	375	388	1,108	1,104
Pension Benefits - Non-U.S. [Member]
Service cost	178	136	524	413
Interest cost	165	189	488	573
Expected return on plan assets	(226)	(192)	(664)	(581)
Amortization of actuarial loss/(gain) and prior service cost	124	102	358	260
Net benefit cost	241	235	706	665
Other Postretirement Benefits [Member]
Service cost	45	38	134	104
Interest cost	70	79	208	237
Expected return on plan assets	(4)	(4)	(13)	(12)
Amortization of actuarial loss/(gain) and prior service cost	13	3	39	10
Net benefit cost	$ 124	$ 116	$ 368	$ 339