Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Equity, beginning balance	$ 38,742	$ 43,318	$ 46,058	$ 38,257
Other comprehensive income (loss) before reclassification adjustments, pretax	24	(230)	63	107
Tax	18	(31)	(48)	(223)
Other comprehensive income (loss) before reclassification adjustments, net of taxes	42	(261)	15	(116)
Reclassification adjustments, pretax	(72)	(177)	(206)	(227)
Tax	14	22	43	29
Reclassification adjustments, net of taxes	(58)	(155)	(163)	(198)
Other comprehensive income (loss), net of taxes	(16)	(416)	(148)	(314)
Equity, ending balance	41,300	44,524	41,300	44,524
Derivatives
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Equity, beginning balance	85	390	73	144
Other comprehensive income (loss) before reclassification adjustments, pretax	247	682	375	1,233
Tax	(52)	(143)	(79)	(259)
Other comprehensive income (loss) before reclassification adjustments, net of taxes	195	539	296	974
Reclassification adjustments, pretax	(45)	(254)	(158)	(493)
Tax	9	53	33	103
Reclassification adjustments, net of taxes	(36)	(201)	(125)	(390)
Other comprehensive income (loss), net of taxes	159	338	171	584
Equity, ending balance	244	728	244	728
Employee Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Equity, beginning balance	(2,483)	(2,465)	(2,408)	(2,743)
Other comprehensive income (loss) before reclassification adjustments, pretax	29	(294)	(24)	(125)
Tax	(7)	62	(4)	25
Other comprehensive income (loss) before reclassification adjustments, net of taxes	22	(232)	(28)	(100)
Reclassification adjustments, pretax	(27)	77	(57)	266
Tax	5	(31)	10	(74)
Reclassification adjustments, net of taxes	(22)	46	(47)	192
Other comprehensive income (loss), net of taxes	0	(186)	(75)	92
Equity, ending balance	(2,483)	(2,651)	(2,483)	(2,651)
Foreign Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Equity, beginning balance	(2,502)	(2,252)	(2,433)	(1,830)
Other comprehensive income (loss) before reclassification adjustments, pretax	(252)	(618)	(288)	(1,001)
Tax	77	50	35	11
Other comprehensive income (loss) before reclassification adjustments, net of taxes	(175)	(568)	(253)	(990)
Reclassification adjustments, pretax	0	0	9	0
Tax	0	0	0	0
Reclassification adjustments, net of taxes	0	0	9	0
Other comprehensive income (loss), net of taxes	(175)	(568)	(244)	(990)
Equity, ending balance	(2,677)	(2,820)	(2,677)	(2,820)
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Equity, beginning balance	(4,900)	(4,327)	(4,768)	(4,429)
Equity, ending balance	$ (4,916)	$ (4,743)	$ (4,916)	$ (4,743)