Note 11: Guarantees (Details) (USD $) In Millions	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Notes to Condensed Consolidated Financial Statements [Abstract]
Service and product warranties and product performance guarantees - beginning of year	$ 1,136	$ 1,072
Warranties and performance guarantees issued	370	310
Settlements made	(333)	(271)
Product warranty accrual - other	315	(6)
Service and product warranties and product performance guarantees - end of period	$ 1,488	$ 1,105

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 15

-Subparagraph 5

-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 9, 10

+ Details

Name:	us-gaap_ProductWarrantyAccrual
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the aggregate decrease in the liability related to payments to satisfy claims for standard and extended product warranties.

+ Details

Name:	us-gaap_ProductWarrantyAccrualPayments
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the aggregate increase in the liability for accruals related to standard and extended product warranties issued during the reporting period.

+ Details

Name:	us-gaap_ProductWarrantyAccrualWarrantiesIssued
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	utx_NotesToCondensedConsolidatedFinancialStatementsAbstract
Namespace Prefix:	utx
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the aggregate increase (decrease) in the liability related to other items, including currency translation.

+ Details

Name:	utx_ProductWarrantyAccrualOther
Namespace Prefix:	utx
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration