Details of Pass Through Trusts (Detail) - United Airlines, Inc. $ in Millions	9 Months Ended
Sep. 30, 2016 USD ($)
Class AA Pass Through Certificates \| September Twenty Sixteen [Member]
Debt Instrument [Line Items]
Principal	$ 637
Final expected distribution date	2028-10
Stated interest rate	2.875%
Remaining proceeds from issuance of debt to be received in future periods	$ 637
Class AA Pass Through Certificates \| June 2016
Debt Instrument [Line Items]
Principal	$ 729
Final expected distribution date	2028-07
Stated interest rate	3.10%
Total debt recorded	$ 222
Remaining proceeds from issuance of debt to be received in future periods	507
Class A Pass Through Certificates \| September Twenty Sixteen [Member]
Debt Instrument [Line Items]
Principal	$ 283
Final expected distribution date	2028-10
Stated interest rate	3.10%
Remaining proceeds from issuance of debt to be received in future periods	$ 283
Class A Pass Through Certificates \| June 2016
Debt Instrument [Line Items]
Principal	$ 324
Final expected distribution date	2028-07
Stated interest rate	3.45%
Total debt recorded	$ 99
Remaining proceeds from issuance of debt to be received in future periods	225
EETC
Debt Instrument [Line Items]
Principal	1,973
Total debt recorded	321
Remaining proceeds from issuance of debt to be received in future periods	$ 1,652

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-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

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