Number of persons employed by the Entity

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- Definition

Debt instrument maturity year

+ References

No definition available.

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Years remaining on debt instruments.

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- Definition

Number of Aircraft under Financing Arrangement Expected to be Delivered

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- Definition

Percentage of employees represented by labor organizations

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No definition available.

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- Definition

Scheduled Delivery Year

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No definition available.

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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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-Publisher FASB

-Name Accounting Standards Codification

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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-Publisher FASB

-Name Accounting Standards Codification

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Commitments and Contingencies - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014 Employee	Dec. 31, 2013
Commitments and Contingencies [Line Items]
Debt instrument principal amount	$ 248,000,000us-gaap_DebtInstrumentCarryingAmount
Floating Rate Debt
Commitments and Contingencies [Line Items]
Debt instrument principal amount	2,500,000,000
Fixed Rate Debt
Commitments and Contingencies [Line Items]
Debt instrument principal amount	159,000,000
Loans And Leases From Non-U.S Entities
Commitments and Contingencies [Line Items]
Debt instrument principal amount	2,700,000,000
Tax-exempt special facilities revenue bonds
Commitments and Contingencies [Line Items]
Guarantor obligations, maximum exposure	1,800,000,000
Operating leases obligations	1,500,000,000
Capital leases obligations	290,000,000
Tax-exempt special facilities revenue bonds \| Indirect Guarantee of Indebtedness
Commitments and Contingencies [Line Items]
Guarantor obligations, maximum exposure	1,400,000,000
Contingent liabilities based on participation	239,000,000
Minimum \| Tax-exempt special facilities revenue bonds
Commitments and Contingencies [Line Items]
Debt instrument maturity year	2015
Minimum \| Tax-exempt special facilities revenue bonds \| Indirect Guarantee of Indebtedness
Commitments and Contingencies [Line Items]
Debt instrument maturity year	2015
Maximum
Commitments and Contingencies [Line Items]
Debt instrument, remaining terms (years)	12 years
Maximum \| Loans And Leases From Non-U.S Entities
Commitments and Contingencies [Line Items]
Debt instrument, remaining terms (years)	12 years
Maximum \| Tax-exempt special facilities revenue bonds
Commitments and Contingencies [Line Items]
Debt instrument maturity year	2038
Maximum \| Tax-exempt special facilities revenue bonds \| Indirect Guarantee of Indebtedness
Commitments and Contingencies [Line Items]
Debt instrument maturity year	2041
United Airlines, Inc.
Commitments and Contingencies [Line Items]
Debt instrument principal amount	$ 11,533,000,000	$ 11,604,000,000
Number of employees	84,000
Percentage of employees represented by various U.S. labor organizations	80.00%
Capital Addition Purchase Commitments \| United Airlines, Inc.
Commitments and Contingencies [Line Items]
Number of aircraft under financing arrangement expected to be delivered	20
Capital Addition Purchase Commitments \| United Airlines, Inc. \| Boeing 787-9 aircraft
Commitments and Contingencies [Line Items]
Number of aircraft under financing arrangement expected to be delivered	4
Capital Addition Purchase Commitments \| United Airlines, Inc. \| Embraer E175 Aircraft
Commitments and Contingencies [Line Items]
Number of aircraft under financing arrangement expected to be delivered	5
Capital Addition Purchase Commitments \| United Airlines, Inc. \| Boeing 737-900ER aircraft
Commitments and Contingencies [Line Items]
Number of aircraft under financing arrangement expected to be delivered	11
Capital Addition Purchase Commitments \| United Airlines, Inc. \| Minimum
Commitments and Contingencies [Line Items]
New aircraft, scheduled delivery date	2015
Capital Addition Purchase Commitments \| United Airlines, Inc. \| Maximum
Commitments and Contingencies [Line Items]
New aircraft, scheduled delivery date	2025