Accumulated Other Comprehensive Income/(Loss) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Derivative instruments [Abstract]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	$ 11
Pension and other postretirement benefits
Total AOCI ending balance at March 31	(8,294)		$ (8,339)
Parent Company [Member]
Foreign currency transaction [Abstract]
Beginning balance	(5,487)	$ (5,526)
Gains/(Losses) on foreign currency translation	(71)	394
Less: Tax/(Tax benefit) (a)	(96)	97
Net gains/(losses) on foreign currency translation	25	297
(Gains)/Losses reclassified from AOCI to income	121	(8)
Other comprehensive income/(loss), net of tax	146	289
Ending balance	(5,341)	(5,237)
Marketable securities [Abstract]
Beginning balance	(19)	156
Gains/(Losses) on available for sale securities	(330)	(76)
Less: Tax/(Tax benefit)	(77)	(19)
Net gains/(losses) on available for sale securities	(253)	(57)
(Gains)/Losses reclassified from AOCI to net income	0	(11)
Less: Tax/(Tax benefit)	0	(3)
Net (gains)/losses reclassified from AOCI to net income	0	(8)
Other comprehensive income/(loss), net of tax	(253)	(65)
Ending balance	(272)	91
Derivative instruments [Abstract]
Beginning balance	(193)	(266)
Gains/(losses) on derivative instruments	156	(381)
Less: Tax/(tax benefit)	37	(74)
Net gains/(losses) on derivative instruments	119	(307)
(Gains)/Losses reclassified from AOCI to net income	32	7
Less: Tax/(tax benefit)	7	1
Net (gains)/losses reclassified to AOCI from net income	25	6
Other comprehensive income/(loss), net of tax	144	(301)
Ending balance	(49)	(567)
Pension and other postretirement benefits
Beginning balance	(2,640)	(2,658)
Amortization of prior service costs/(credits)	6	3
Less: Tax/(Tax benefit)	1	1
Net prior service costs/(credits) reclassified from AOCI to net income	5	2
Translation impact on non-U.S. plans	3	(1)
Other comprehensive income/(loss), net of tax	8	1
Ending balance	(2,632)	(2,657)
Total AOCI ending balance at March 31	$ (8,294)	$ (8,370)