v3.19.3.a.u2
Cover - USD ($)
12 Months Ended
Dec. 31, 2019
Jan. 31, 2020
Jun. 30, 2019
Document Information [Line Items]      
Document Type 10-K    
Amendment Flag false    
Document Fiscal Year Focus 2019    
Document Fiscal Period Focus FY    
Current Fiscal Year End Date --12-31    
Document Transition Report false    
Entity Address, Country US    
Entity Central Index Key 0000101829    
Document Annual Report true    
Document Period End Date Dec. 31, 2019    
Entity File Number 1-812    
Entity Registrant Name UNITED TECHNOLOGIES CORPORATION    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 06-0570975    
Entity Address, Address Line One 10 Farm Springs Road,    
Entity Address, City or Town Farmington,    
Entity Address, State or Province CT    
Entity Address, Postal Zip Code 06032    
City Area Code (860)    
Local Phone Number 728-7000    
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Large Accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
Entity Shell Company false    
Entity Public Float     $ 112,271,798,129
Entity Common Stock, Shares Outstanding   865,308,981  
Documents Incorporated by Reference [Text Block]
DOCUMENTS INCORPORATED BY REFERENCE
Parts I, II and IV hereof incorporate by reference portions of the United Technologies Corporation 2019 Annual Report to Shareowners. Part III hereof incorporates by reference portions of the United Technologies Corporation Proxy Statement for the 2020 Annual Meeting of Shareowners.
   
Common Stock [Member]      
Document Information [Line Items]      
Title of 12(b) Security Common Stock ($1 par value)    
Trading Symbol UTX    
Security Exchange Name NYSE    
Notes 1.125% Due 2021 [Member]      
Document Information [Line Items]      
Title of 12(b) Security 1.125% Notes due 2021    
Trading Symbol UTX 21D    
Security Exchange Name NYSE    
Notes 1.250% due 2023 [Member]      
Document Information [Line Items]      
Title of 12(b) Security 1.250% Notes due 2023    
Trading Symbol UTX 23    
Security Exchange Name NYSE    
Notes 1.150% Due 2024 [Member]      
Document Information [Line Items]      
Title of 12(b) Security 1.150% Notes due 2024    
Trading Symbol UTX 24A    
Security Exchange Name NYSE    
Notes 1.875% Due 2026 [Member]      
Document Information [Line Items]      
Title of 12(b) Security 1.875% Notes due 2026    
Trading Symbol UTX 26    
Security Exchange Name NYSE    
Notes 2.150% Due 2030 [Member]      
Document Information [Line Items]      
Title of 12(b) Security 2.150% Notes due 2030    
Trading Symbol UTX 30    
Security Exchange Name NYSE    
Floating Rate Notes Due2020 [Member]      
Document Information [Line Items]      
Title of 12(b) Security Floating Rate Notes due 2020    
Trading Symbol UTX 20B    
Security Exchange Name NYSE