Contractual Principal Payments Under then-Outstanding Long Term Debt (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013
Debt Instrument [Line Items]
Last six months of 2013	$ 455
2014	940
2015	2,037
2016	1,014
2017	577
After 2017	6,260
Long-term debt	11,283
United Airlines, Inc.
Debt Instrument [Line Items]
Last six months of 2013	455
2014	940
2015	2,037
2016	1,014
2017	577
After 2017	6,104
Long-term debt	$ 11,127

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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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-Publisher SEC

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-Number 210

-Section 03

-Paragraph 16

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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 next fiscal year following the latest fiscal year.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

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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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