Description of the terms of a credit facility arrangement. Terms typically include interest rate, collateral required, guarantees required, repayment requirements, and restrictions on use of assets and activities of the entity.

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Balance Type:	na
Period Type:	duration

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Date the credit facility first became available, in CCYY-MM-DD format.

+ References

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum month-end amount borrowed under the credit facility during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Definite liabilities to third parties under a termination loan agreement, whether or not guaranteed in whole or in part by the government.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 912
-SubTopic 405
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68073528&loc=d3e56288-109415

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

Name:	utx_AggregateLineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	utx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Euro-denominated Commercial paper - carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

+ References

No definition available.

+ Details

Name:	utx_Commercialpapereurodenominated
Namespace Prefix:	utx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The maximum amount of commercial paper borrowing authority fir general corporate purposes, including the funding of potential acquisitions and repurchases of common stock.

+ References

No definition available.

+ Details

Name:	utx_MaximumCommercialPaperBorrowingAuthority
Namespace Prefix:	utx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Termination Date

+ References

No definition available.

+ Details

Name:	utx_TerminationDate
Namespace Prefix:	utx_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_CreditFacilityAxis=utx_RevolvingCreditAgreementMember
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- Details

Name:	us-gaap_CreditFacilityAxis=utx_MultiCurrencyRevolvingCreditAgreementMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
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- Details

Name:	us-gaap_CreditFacilityAxis=utx_A1.5BRevolvingCreditAgreementMember
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Borrowing and Lines of Credit (Narrative) (Details) € in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2019 EUR (€)
Line of Credit Facility [Line Items]
Aggregate Line of Credit Agreements, Maximum Borrowing Capacity	$ 10,350,000,000	$ 10,350,000,000
Maximum Commercial Paper Borrowing Authority	6,350,000,000	6,350,000,000
Commercial paper, euro-denominated	855,000,000	855,000,000	€ 750
2.20B Revolving Credit Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	2,200,000,000	$ 2,200,000,000
Line of Credit Facility, Expiration Date		Aug. 05, 2021
Borrowings under credit agreements	0
2.15B Multicurrency Revolving Credit Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	2,150,000,000	$ 2,150,000,000
Line of Credit Facility, Expiration Date		Aug. 05, 2021
Borrowings under credit agreements	0
2.0B Revolving Credit Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	2,000,000,000.0	$ 2,000,000,000.0
Line of Credit Facility, Expiration Date		Mar. 15, 2021
Line of Credit Facility, Expiration Terms		180 days after the date on which each of the separations of Otis and Carrier have been consummated
Line of Credit Facility, Initiation Date		Mar. 15, 2019
Borrowings under credit agreements	0
4.0B Term Credit Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	4,000,000,000.0	$ 4,000,000,000.0
Line of Credit Facility, Expiration Date		Mar. 15, 2021
Line of Credit Facility, Expiration Terms		180 days after the date on which each of the separations of Otis and Carrier have been consummated
Line of Credit Facility, Initiation Date		Mar. 15, 2019
Borrowings under credit agreements	0
1.5B Revolving Credit Agreement [Member]
Line of Credit Facility [Line Items]
Termination Date		Mar. 15, 2019
Termination Loans	1,500,000,000	$ 1,500,000,000
Borrowings under credit agreements	$ 0