Credit agreement covenants minimum liquidity requirement value.

No definition available.

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- Definition

Increase in term loan balance.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Longterm Debt Maturities Repayments of Principal in Quarterly Installments Percent

+ References

No definition available.

+ Details

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- Definition

Revolving credit facility appraised value of collateral to outstanding obligations ratio.

+ References

No definition available.

+ Details

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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.

+ Details

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Balance Type:	na
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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

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

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	instant

- 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

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

- Definition

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

+ 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(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	duration

- 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=6479336&loc=d3e64711-112823

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

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

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	na
Period Type:	duration

- 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

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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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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Period Type:	duration

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- Details

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Debt - Additional Information (Detail)	1 Months Ended	3 Months Ended
Debt - Additional Information (Detail)	Jan. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)
Credit Agreement
Debt Instrument [Line Items]
Minimum ratio of appraised value of collateral to the outstanding obligations		1.60
Credit Agreement \| Minimum
Debt Instrument [Line Items]
Credit Agreement Covenants Minimum Liquidity Requirement Value		$ 2,000,000,000
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. \| Revolving Credit Facility
Debt Instrument [Line Items]
Commitment fee percentage		0.75%
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] \| Interest Rate Floor
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		0.00%
United Airlines, Inc. \| Secured Debt \| Term Loan Due April 1, 2024 [Member] \| LIBOR
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		2.25%
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		1.25%
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
United Airlines, Inc. \| Secured Debt \| Revolving Credit Facility
Debt Instrument [Line Items]
Credit agreement		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