Activity for "Level Three" Financial Assets and Financial Liabilities (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011
United Continental Holdings Inc | Auction Rate Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	$ 112	[1]	$ 121	[1]	$ 113	[1]	$ 119	[1]
Reported in earnings-unrealized	1	[1]	1	[1]			2	[1]
Reported in other comprehensive income (loss)	2	[1]	(1)	[1]	2	[1]
Ending Balance	115	[1]	121	[1]	115	[1]	121	[1]
United Continental Holdings Inc | EETC
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	63	[1]	65	[1]	60	[1]	66	[1]
Settlements	(2)	[1]	(2)	[1]	(5)	[1]	(4)	[1]
Reported in other comprehensive income (loss)	1	[1]	(3)	[1]	7	[1]	(2)	[1]
Ending Balance	62	[1]	60	[1]	62	[1]	60	[1]
Continental Airlines Inc | Auction Rate Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	112		121		113		119
Sales
Reported in earnings-unrealized	1		1				2
Reported in other comprehensive income (loss)	2		(1)		2
Ending Balance	115		121		115		121
Continental Airlines Inc | Convertible Debt Derivative Asset
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	289	[2]	251	[2]	193	[2]	286	[2]
Sales		[2]		[2]		[2]		[2]
Reported in earnings-unrealized	(87)	[2]	(52)	[2]	9	[2]	(87)	[2]
Ending Balance	202	[2]	199	[2]	202	[2]	199	[2]
Continental Airlines Inc | Convertible Debt Option Liability
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	(147)	[2]	(143)	[2]	(95)	[2]	(164)	[2]
Sales		[2]		[2]		[2]		[2]
Reported in earnings-unrealized	56	[2]	40	[2]	4	[2]	61	[2]
Ending Balance	$ (91)	[2]	$ (103)	[2]	$ (91)	[2]	$ (103)	[2]

[1] For 2012 and 2011, United's only Level 3 recurring measurements are the above EETCs.

[2] These derivatives are not designated as hedges. The Convertible Debt Supplemental Derivative Asset is classified in "Other Asset-Other, net", and the Convertible Debt Conversion Option Liability is classified in "Other liabilities and deferred credits-Other" in Continental's consolidated balance sheets. The earnings impact is classified in "Nonoperating income (expense)-Miscellaneous, net" in Continental's statements of consolidated operations.