Changes in Accumulated Other Comprehensive Losses (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ 160,434	$ 147,100	$ 160,242	$ 139,940
Components of Other Comprehensive Income (Loss):
Other Comprehensive Gain (Loss), Net of Tax	30	161	87	398
Ending balance	159,298	154,562	159,298	154,562
Related income taxes	1,829	4,288	4,743	7,065
Total
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(2,741)	(3,652)	(2,798)	(3,889)
Components of Other Comprehensive Income (Loss):
Before Reclassifications			6	207
Reclassifications			81	191
Other Comprehensive Gain (Loss), Net of Tax	30	161	87	398
Ending balance	(2,711)	(3,491)	(2,711)	(3,491)
Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			(203)	(162)
Components of Other Comprehensive Income (Loss):
Before Reclassifications			0	(48)
Reclassifications			0	0
Other Comprehensive Gain (Loss), Net of Tax			0	(48)
Ending balance	(203)	(210)	(203)	(210)
Unrealized Holding Gains (Losses) on Securities
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			(12)	(11)
Components of Other Comprehensive Income (Loss):
Before Reclassifications			(3)	0
Reclassifications			0	0
Other Comprehensive Gain (Loss), Net of Tax			(3)	0
Ending balance	(15)	(11)	(15)	(11)
Derivatives
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			(12)	0
Components of Other Comprehensive Income (Loss):
Before Reclassifications			(5)	24
Reclassifications			13	(2)
Other Comprehensive Gain (Loss), Net of Tax			8	22
Ending balance	(4)	22	(4)	22
Defined Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			(2,571)	(3,716)
Components of Other Comprehensive Income (Loss):
Before Reclassifications			14	231
Reclassifications			68	193
Other Comprehensive Gain (Loss), Net of Tax			82	424
Ending balance	$ (2,489)	$ (3,292)	(2,489)	$ (3,292)
Defined Benefit Plans | Reclassification out of Accumulated Other Comprehensive Income
Components of Other Comprehensive Income (Loss):
Employee Benefits for reclassified components			89
Related income taxes			$ 21