Restructuring and Other Costs (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			9 Months Ended	12 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Sep. 30, 2014	Dec. 31, 2013
Restructuring Cost and Reserve [Line Items]
Net pre-tax restructuring costs				$ 243
Restructuring Reserve, Two Years Prior Actions	55			55
Current Year Actions [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve Beginning Balance	113
Net pre-tax restructuring costs	64			215
Utilization and foreign exchange	(56)
Restructuring Reserve Ending Balance	121	113		121
Restructuring and Related Cost, Incurred Cost	(64)	(61)	(90)
Restructuring and Related Cost, Expected Cost	314			314
Restructuring And Related Cost Expected Remaining	99			99
Current Year Actions [Member] | Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve Beginning Balance	112
Net pre-tax restructuring costs	43
Utilization and foreign exchange	(45)
Restructuring Reserve Ending Balance	110			110
Current Year Actions [Member] | Asset Write-Downs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve Beginning Balance	0
Net pre-tax restructuring costs	4
Utilization and foreign exchange	(4)
Restructuring Reserve Ending Balance	0			0
Current Year Actions [Member] | Facility Exit, Lease Termination and Other Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve Beginning Balance	1
Net pre-tax restructuring costs	17
Utilization and foreign exchange	(7)
Restructuring Reserve Ending Balance	11			11
Prior Year Actions [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve Beginning Balance	155
Net pre-tax restructuring costs	0			33
Utilization and foreign exchange	(32)
Restructuring Reserve Ending Balance	123	155		123
Restructuring and Related Cost, Incurred Cost	0	(1)	(32)		(421)
Restructuring and Related Cost, Expected Cost	480			480
Restructuring And Related Cost Expected Remaining	26			26
Prior Year Actions [Member] | Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve Beginning Balance	132
Net pre-tax restructuring costs	(4)
Utilization and foreign exchange	(26)
Restructuring Reserve Ending Balance	102			102
Prior Year Actions [Member] | Asset Write-Downs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve Beginning Balance	0
Net pre-tax restructuring costs	0
Utilization and foreign exchange	0
Restructuring Reserve Ending Balance	0			0
Prior Year Actions [Member] | Facility Exit, Lease Termination and Other Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve Beginning Balance	23
Net pre-tax restructuring costs	4
Utilization and foreign exchange	(6)
Restructuring Reserve Ending Balance	21			21
Otis [Member]
Restructuring Cost and Reserve [Line Items]
Net pre-tax restructuring costs				53
Otis [Member] | Current Year Actions [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	(17)	(28)	(18)
Restructuring and Related Cost, Expected Cost	85			85
Restructuring And Related Cost Expected Remaining	22			22
Otis [Member] | Prior Year Actions [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	0	2	(1)		(69)
Restructuring and Related Cost, Expected Cost	69			69
Restructuring And Related Cost Expected Remaining	1			1
UTC Climate, Controls and Security [Member]
Restructuring Cost and Reserve [Line Items]
Net pre-tax restructuring costs				82
UTC Climate, Controls and Security [Member] | Current Year Actions [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	(16)	(21)	(16)
Restructuring and Related Cost, Expected Cost	97			97
Restructuring And Related Cost Expected Remaining	44			44
UTC Climate, Controls and Security [Member] | Prior Year Actions [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	2	(2)	(24)		(89)
Restructuring and Related Cost, Expected Cost	124			124
Restructuring And Related Cost Expected Remaining	11			11
Pratt and Whitney [Member]
Restructuring Cost and Reserve [Line Items]
Net pre-tax restructuring costs				55
Pratt and Whitney [Member] | Current Year Actions [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	(8)	(10)	(37)
Restructuring and Related Cost, Expected Cost	78			78
Restructuring And Related Cost Expected Remaining	23			23
Pratt and Whitney [Member] | Prior Year Actions [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	0	1	(6)		(154)
Restructuring and Related Cost, Expected Cost	163			163
Restructuring And Related Cost Expected Remaining	4			4
UTC Aerospace Systems [Member]
Restructuring Cost and Reserve [Line Items]
Net pre-tax restructuring costs				36
UTC Aerospace Systems [Member] | Current Year Actions [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	(22)	(2)	(3)
Restructuring and Related Cost, Expected Cost	37			37
Restructuring And Related Cost Expected Remaining	10			10
UTC Aerospace Systems [Member] | Prior Year Actions [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	(3)	(3)	(1)		(71)
Restructuring and Related Cost, Expected Cost	88			88
Restructuring And Related Cost Expected Remaining	10			10
Sikorsky [Member]
Restructuring Cost and Reserve [Line Items]
Net pre-tax restructuring costs				17
Sikorsky [Member] | Current Year Actions [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	(1)	0	(16)
Restructuring and Related Cost, Expected Cost	17			17
Restructuring And Related Cost Expected Remaining	0			0
Sikorsky [Member] | Prior Year Actions [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Incurred Cost	1	1	0		(38)
Restructuring and Related Cost, Expected Cost	36			36
Restructuring And Related Cost Expected Remaining	0			0
Cost Of Sales [Member]
Restructuring Cost and Reserve [Line Items]
Net pre-tax restructuring costs				136
Cost Of Sales [Member] | Current Year Actions [Member]
Restructuring Cost and Reserve [Line Items]
Net pre-tax restructuring costs				109
Cost Of Sales [Member] | Prior Year Actions [Member]
Restructuring Cost and Reserve [Line Items]
Net pre-tax restructuring costs				29
Selling General and Administrative [Member]
Restructuring Cost and Reserve [Line Items]
Net pre-tax restructuring costs				107
Selling General and Administrative [Member] | Current Year Actions [Member]
Restructuring Cost and Reserve [Line Items]
Net pre-tax restructuring costs				106
Selling General and Administrative [Member] | Prior Year Actions [Member]
Restructuring Cost and Reserve [Line Items]
Net pre-tax restructuring costs				$ 4