Acquisitions, Dispositions, Goodwill and Other Intangible Assets Pro Forma Financial Data (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenues	$ 19,634,000,000	$ 16,705,000,000	$ 37,999,000,000	$ 31,947,000,000
Operating profit	2,584,000,000	2,876,000,000	4,629,000,000	4,804,000,000
Rockwell Collins [Member]
Revenues			4,600,000,000
Operating profit			665,000,000
Business Acquisition, Pro Forma Revenue	19,634,000,000	18,810,000,000	37,994,000,000	36,131,000,000
Business Acquisition, Pro Forma Net Income	$ 1,901,000,000	$ 2,266,000,000	$ 3,385,000,000	$ 3,742,000,000
Business Acquisition, Pro Forma Earnings Per Share, Basic	$ 2.22	$ 2.66	$ 3.96	$ 4.39
Business Acquisition, Pro Forma Earnings Per Share, Diluted	$ 2.20	$ 2.63	$ 3.92	$ 4.34
Pro Forma Nonrecurring Adjustment, Amortization of inventory and fixed asset fair value adjustment	$ 0	$ (5,000,000)	$ 141,000,000	$ (10,000,000)
Pro Forma Nonrecurring Adjustment, Amortization of acquired Rockwell Collins intangible assets, net	0	(53,000,000)	0	(106,000,000)
Pro Forma Nonrecurring Adjustment, Utilization of contractual customer obligation	0	8,000,000	0	10,000,000
Pro Forma Nonrecurring Adjustment, UTC/Rockwell fees for advisory, legal, accounting services	1,000,000	17,000,000	3,000,000	43,000,000
Pro Forma Nonrecurring Adjustment, Interest expense incurred on acquisition financing, net	0	(76,000,000)	0	(152,000,000)
Pro Forma Nonrecurring Adjustment, Elimination of capitalized pre-production engineering amortization	0	17,000,000	0	32,000,000
Pro Forma Nonrecurring Adjustment, Adjustment to net periodic pension cost	0	11,000,000	0	22,000,000
Pro Forma Nonrecurring Adjustment, Adjustment to reflect the adoption of ASC 606	0	29,000,000	0	58,000,000
Pro Forma Nonrecurring Adjustment, Elimination of entities held for sale	0	(5,000,000)	(5,000,000)	(12,000,000)
Pro Forma Nonrecurring Adjustments, Net	$ 1,000,000	$ (57,000,000)	$ 139,000,000	$ (115,000,000)