Segment Financial Data (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Revenues	$ 19,634	$ 16,705	$ 37,999	$ 31,947
Operating profit	$ 2,584	$ 2,876	$ 4,629	$ 4,804
Operating Profit Margin	13.20%	17.20%	12.20%	15.00%
Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	$ 5,150	$ 4,736	$ 9,967	$ 9,065
Operating profit	$ 424	$ 397	$ 857	$ 810
Operating Profit Margin	8.20%	8.40%	8.60%	8.90%
Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	$ 20,036	$ 17,077	$ 38,785	$ 32,636
Operating profit	$ 2,947	$ 3,099	$ 5,191	$ 5,142
Operating Profit Margin	14.70%	18.10%	13.40%	15.80%
Otis [Member]
Segment Reporting Information [Line Items]
Revenues	$ 3,348	$ 3,344	$ 6,444	$ 6,381
Operating profit	$ 515	$ 488	$ 941	$ 938
Operating Profit Margin	15.40%	14.60%	14.60%	14.70%
Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	$ 4,962	$ 5,035	$ 9,285	$ 9,411
Operating profit	$ 836	$ 1,645	$ 1,365	$ 2,237
Operating Profit Margin	16.80%	32.70%	14.70%	23.80%
Eliminations and other [Member]
Segment Reporting Information [Line Items]
Revenues	$ (402)	$ (372)	$ (786)	$ (689)
Operating profit	(239)	(97)	(340)	(108)
General corporate expenses [Member]
Segment Reporting Information [Line Items]
Revenues	0	0	0	0
Operating profit	(124)	(126)	(222)	(230)
Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	6,576	3,962	13,089	7,779
Operating profit	$ 1,172	$ 569	$ 2,028	$ 1,157
Operating Profit Margin	17.80%	14.40%	15.50%	14.90%
United States [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	$ 3,967	$ 3,652	$ 7,699	$ 6,773
United States [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	12,375	9,905	23,963	18,620
United States [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	904	859	1,816	1,704
United States [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	2,707	2,618	4,921	4,713
United States [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	4,797	2,776	9,527	5,430
Europe [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	112	126	221	299
Europe [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	3,393	3,220	6,772	6,389
Europe [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	992	1,054	1,947	2,059
Europe [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	1,301	1,455	2,593	2,839
Europe [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	988	585	2,011	1,192
Asia Pacific [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	294	312	549	680
Asia Pacific [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	2,441	2,286	4,473	4,345
Asia Pacific [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	1,200	1,169	2,176	2,091
Asia Pacific [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	737	720	1,349	1,405
Asia Pacific [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	210	85	399	169
Other [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	777	646	1,498	1,313
Other [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	1,827	1,666	3,577	3,282
Other [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	252	262	505	527
Other [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	217	242	422	454
Other [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	581	516	1,152	988
Commercial and industrial, non aerospace [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	5	5	28	26
Commercial and industrial, non aerospace [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	8,327	8,399	15,783	15,848
Commercial and industrial, non aerospace [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	3,348	3,344	6,444	6,381
Commercial and industrial, non aerospace [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	4,962	5,035	9,285	9,411
Commercial and industrial, non aerospace [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	12	15	26	30
Commercial Aerospace [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	3,538	3,369	6,913	6,568
Commercial Aerospace [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	8,393	6,393	16,596	12,503
Commercial Aerospace [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	0	0	0	0
Commercial Aerospace [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	0	0	0	0
Commercial Aerospace [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	4,855	3,024	9,683	5,935
Military aerospace [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	1,607	1,362	3,026	2,471
Military aerospace [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	3,316	2,285	6,406	4,285
Military aerospace [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	0	0	0	0
Military aerospace [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	0	0	0	0
Military aerospace [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	1,709	923	3,380	1,814
Service [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	1,845	1,961	3,689	3,753
Service [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	5,642	5,224	11,165	10,241
Service [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	1,837	1,819	3,653	3,637
Service [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	824	822	1,580	1,600
Service [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	1,136	622	2,243	1,251
Product [Member] | Pratt & Whitney [Member]
Segment Reporting Information [Line Items]
Revenues	3,305	2,775	6,278	5,312
Product [Member] | Total Segments [Member]
Segment Reporting Information [Line Items]
Revenues	14,394	11,853	27,620	22,395
Product [Member] | Otis [Member]
Segment Reporting Information [Line Items]
Revenues	1,511	1,525	2,791	2,744
Product [Member] | Carrier [Member]
Segment Reporting Information [Line Items]
Revenues	4,138	4,213	7,705	7,811
Product [Member] | Collins Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Revenues	$ 5,440	$ 3,340	$ 10,846	$ 6,528