Accumulated Other Comprehensive Income (Loss) (Summary of Changes in AOCI) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	$ 49	$ 710	$ (3,211)	$ (3,442)
Other comprehensive (loss) income, net - Foreign Currency Translation	(647)	609	280
Amounts reclassified, pretax - Foreign Currency Translation	0	0	2
Tax benefit (expense)	(14)	25	(43)
Other Comprehensive Income (Loss), ASU 2018-02 adoption impact on foreign currency translation Arising During Period			(8)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Impact of Separation of Carrier and Otis, net of Tax		3,287
Other Comprehensive Income (Loss), Defined Benefit Plan, Impact of Separation of Carrier and Otis, net of Tax		584
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax	(1,828)	(4,483)	(6,772)	(5,718)
Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment and Tax	3,210	1,842	(584)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, before Tax	258	373	170
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax	(813)	(510)	97
Other Comprehensive Income (Loss), ASU 2018-02 adoption impact on Defined Benefit Plan Arising During Period			(737)
AOCI, Cash Flow Hedge, Cumulative Gain (Loss), after Tax	(136)	39	(166)	(173)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax	(226)	181	(33)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	(28)	82	51
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax	79	(62)	(11)
Other Comprehensive Income (Loss), ASU 2018-02 adoption impact on Derivatives Arising During Period			0
Other Comprehensive Income (Loss), Cash Flow Hedge, Impact of Separation of Carrier and Otis, net of Tax		4
Other comprehensive (loss) income before reclassifications, net	2,337	2,632	(337)
Amounts reclassified, pretax	230	455	223
Other Comprehensive Income (Loss), Tax	748	547	(43)
Reclassification from OCI, current period, ASU 2018-02 adoption impact			(745)
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (1,915)	(3,734)	$ (10,149)	$ (9,333)
Other Comprehensive Income (Loss), Impact of Separation of Carrier and Otis, net of Tax		$ 3,875