Acquisitions, Dispositions, Goodwill and Other Intangible Assets(Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2014
Business Acquisition [Line Items]
Acquisition Cost Of Acquired Entities and Interest in Affiliates	$ 17

The total cost of acquired entities and interest in affiliates including the cash paid to shareholders, fair value of debt and equity securities issued to shareholders, the fair value of the liabilities assumed, and direct costs of the acquisitions and interest in affiliates.

No definition available.

Name:	utx_AcquisitionCostOfAcquiredEntitiesAndInterestInAffiliates
Namespace Prefix:	utx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration