Details of Pass Through Trusts (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
Proceeds received from issuance of debt	$ 1,423	$ 1,121	$ 152
United Airlines, Inc.
Debt Instrument [Line Items]
Total debt recorded	11,604	12,059
Proceeds received from issuance of debt	1,423	1,121	152
United Airlines, Inc. | Class A Pass Through Certificates | August 2013
Debt Instrument [Line Items]
Principal	720
Final expected distribution date	2025-08
Stated interest rate	4.30%
Total debt recorded	153
Proceeds received from issuance of debt	153
Remaining proceeds from issuance of debt to be received in future periods	567
United Airlines, Inc. | Class A Pass Through Certificates | October 2012
Debt Instrument [Line Items]
Principal	712
Final expected distribution date	2024-10
Stated interest rate	4.00%
Total debt recorded	712
Proceeds received from issuance of debt	465
United Airlines, Inc. | Class B Pass Through Certificates | August 2013
Debt Instrument [Line Items]
Principal	209
Final expected distribution date	2021-08
Stated interest rate	5.375%
Total debt recorded	44
Proceeds received from issuance of debt	44
Remaining proceeds from issuance of debt to be received in future periods	165
United Airlines, Inc. | Class B Pass Through Certificates | October 2012
Debt Instrument [Line Items]
Principal	132
Final expected distribution date	2020-10
Stated interest rate	5.50%
Total debt recorded	132
Proceeds received from issuance of debt	86
United Airlines, Inc. | Class C Pass Through Certificates | December 2012
Debt Instrument [Line Items]
Principal	425
Final expected distribution date	2018-04
Stated interest rate	6.125%
Total debt recorded	425
Proceeds received from issuance of debt	147
United Airlines, Inc. | EETC
Debt Instrument [Line Items]
Principal	2,198
Total debt recorded	1,466
Proceeds received from issuance of debt	895
Remaining proceeds from issuance of debt to be received in future periods	$ 732