Common Stockholders' Equity and Preferred Securities - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified				2 Months Ended
	Dec. 31, 2013	Nov. 30, 2013 Unsecured Debt	Jun. 30, 2011 United Airlines, Inc. Unsecured Debt	Feb. 20, 2014 Subsequent Event United Airlines, Inc. Unsecured Debt
Schedule Of Stockholders Equity [Line Items]
Common stock reserved for future issuance	44,000,000
Junior preferred stock outstanding	2
Junior preferred stock par value per share	$ 0.01
Preferred stock authorized to issue	250,000,000
Debt instument converted amount				$ 156
Debt instrument stated interest rate		6.00%	4.50%	4.50%
Debt instrument, maturity date				2021
Debt instument convertion rate				30.6419