Increase in term loan balance.

No definition available.

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- Definition

Interest on borrowings, reduction percentage.

+ References

No definition available.

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- Definition

Line Of Credit Facility Maturity Year

+ References

No definition available.

+ Details

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- Definition

Longterm Debt Maturities Repayments of Principal in Quarterly Installments Percent

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- 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.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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+ Details

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- Definition

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

+ References

+ Details

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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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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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Debt - Additional Information (Detail) - USD ($)	1 Months Ended		12 Months Ended
Debt - Additional Information (Detail) - USD ($)	Sep. 30, 2017	Jan. 30, 2017	Dec. 31, 2017	Nov. 30, 2017
4.25% Senior Notes due 2022
Debt Instrument [Line Items]
Debt instrument stated interest rate			4.25%
5% Senior Notes due 2024
Debt Instrument [Line Items]
Debt instrument stated interest rate			5.00%
United Airlines, Inc.
Debt Instrument [Line Items]
Aggregate principal amount			$ 497,000,000
United Airlines, Inc. \| Pass-through certificates
Debt Instrument [Line Items]
Long term debt			8,600,000,000
United Airlines, Inc. \| 4.25% Senior Notes due 2022
Debt Instrument [Line Items]
Aggregate principal amount	$ 400,000,000
Debt instrument maturity date	Oct. 01, 2022
Debt instrument stated interest rate	4.25%
Notes repurchase price	101.00%
United Airlines, Inc. \| 5% Senior Notes due 2024
Debt Instrument [Line Items]
Aggregate principal amount		$ 300,000,000
Debt instrument maturity date		Feb. 01, 2024
Debt instrument stated interest rate		5.00%
Notes repurchase price		101.00%
United Airlines, Inc. \| Surety Bond
Debt Instrument [Line Items]
Credit facility outstanding amount			$ 362,000,000
Credit facility expiration year			2021
United Airlines, Inc. \| Revolving Credit Facility
Debt Instrument [Line Items]
Commitment fee percentage			0.75%
United Airlines, Inc. \| Letters of credit \| Cash Collateralized Letters of Credit
Debt Instrument [Line Items]
Credit facility outstanding amount			$ 75,000,000
United Airlines, Inc. \| Secured Debt
Debt Instrument [Line Items]
Quarterly principal repayment amount			0.25%
United Airlines, Inc. \| Secured Debt \| Term Loan Due April 1, 2024 [Member] \| LIBOR
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate			2.00%
United Airlines, Inc. \| Secured Debt \| Term Loan Due April 1, 2024 [Member] \| Certain Market Interest Rates
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate			1.00%
United Airlines, Inc. \| Secured Debt \| Term Loan Facility Due April 1, 2024
Debt Instrument [Line Items]
Aggregate principal amount			$ 1,500,000,000
Debt instrument maturity date			Apr. 01, 2024
Increase in term loan balance			$ 440,000,000
Interest on borrowings reduction percentage				0.25%
United Airlines, Inc. \| Secured Debt \| Revolving Credit Facility
Debt Instrument [Line Items]
Available under revolving credit facility			2,000,000,000
United Airlines, Inc. \| Secured Debt \| Revolving Credit Facility Available For Drawing Until April 1, 2022
Debt Instrument [Line Items]
Credit agreement			$ 2,000,000,000
Revolving credit facility available for drawing date			Apr. 01, 2022