Contractual Principal Payments (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014
Debt Instrument [Line Items]
Last nine months of 2014	$ 756
2015	2,102
2016	1,083
2017	646
2018	1,168
After 2018	5,682
Long-term debt	11,437
United Airlines, Inc.
Debt Instrument [Line Items]
Last nine months of 2014	756
2015	2,102
2016	1,083
2017	646
2018	1,168
After 2018	5,624
Long-term debt	$ 11,379

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year.

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

-Publisher FASB

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-Topic 470

-SubTopic 10

-Section 50

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the remainder of the fiscal year following the latest fiscal year ended.

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