Statements of Consolidated Stockholder's Equity (Deficit) (USD $) In Millions, except Share data	Total	United Air Lines Inc	Continental Airlines Inc	Continental Airlines Inc Predecessor	Continental Airlines Inc Successor	Common Stock	Common Stock Continental Airlines Inc Predecessor	Common Stock Continental Airlines Inc Successor	Additional Capital Invested	Additional Capital Invested United Air Lines Inc	Additional Capital Invested Continental Airlines Inc Predecessor	Additional Capital Invested Continental Airlines Inc Successor	Treasury Stock	Retained Deficit	Retained Deficit United Air Lines Inc	Retained Deficit Continental Airlines Inc Predecessor	Retained Deficit Continental Airlines Inc Successor	Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss) United Air Lines Inc	Accumulated Other Comprehensive Income (Loss) Continental Airlines Inc Predecessor	Accumulated Other Comprehensive Income (Loss) Continental Airlines Inc Successor
Beginning Balance at Dec. 31, 2009				$ 590			$ 1				$ 2,216					$ (442)				$ (1,185)
Beginning Balance (in shares) at Dec. 31, 2009							139,000,000
Net income (loss)				441												441
Other comprehensive income (loss)				93																93
Share-based compensation				10							10
Proceeds from exercise of stock options (in shares)				1,652,000			2,000,000
Proceeds from exercise of stock options				28							28
Ending Balance at Sep. 30, 2010				1,162			1				2,254					(1)				(1,092)
Ending Balance (in shares) at Sep. 30, 2010							141,000,000
Beginning Balance at Dec. 31, 2009	(2,811)	(2,452)				2			3,136	3,401			(28)	(5,956)	(5,888)			35	35
Beginning Balance (in shares) at Dec. 31, 2009						168,000,000
Net income (loss)	253	399												253	399
Other comprehensive income (loss)	352	56																352	56
Shares issued in exchange for Continental common stock (in shares)						148,000,000
Shares issued in exchange for Continental common stock	3,502					1			3,501
Equity component of Continental convertible debt assumed in Merger	157								157
Shares issued in exchange for redemption of Continental convertible debt (in shares)						9,000,000
Shares issued in exchange for redemption of Continental convertible debt	164								164
Fair value of Continental stock options related to Merger	78								78
Share-based compensation	14	12							14	12
Proceeds from exercise of stock options (in shares)	2,467,000					3,000,000
Proceeds from exercise of stock options	21								21
Capital contributions from parent		8								8
Treasury stock acquisitions	(3)												(3)
Ending Balance at Dec. 31, 2010	1,727	(1,977)				3			7,071	3,421			(31)	(5,703)	(5,489)			387	91
Ending Balance (in shares) at Dec. 31, 2010						328,000,000
Beginning Balance at Sep. 30, 2010
Elimination of equity accounts in connection with the Merger (in shares)								(141,000,000)
Elimination of equity accounts in connection with the Merger					(1,162)			(1)				(2,254)					1				1,092
Net income (loss)					(95)												(95)
Shares issued in exchange for Continental common stock					3,579							3,579
Contribution of indenture derivative asset by UAL					520							520
Other comprehensive income (loss)					290																290
Capital contributions from parent					13							13
Other					3							3
Ending Balance at Dec. 31, 2010	1,727	(1,977)			4,310	3			7,071	3,421		4,115		(5,703)	(5,489)		(95)	387	91		290
Beginning Balance (in shares) at Dec. 31, 2010						328,000,000
Net income (loss)	840	281			569									840	281		569
Other comprehensive income (loss)	(804)	(219)																(804)	(219)
Other comprehensive income (loss)					(587)																(587)
Share-based compensation	17	9			9				17	9		9
Proceeds from exercise of stock options (in shares)	2,449,000					3,000,000
Proceeds from exercise of stock options	26								26
Capital contributions from parent		2			24					2		24
Ending Balance at Dec. 31, 2011	1,806	(1,904)	4,325		4,325	3			7,114	3,432		4,148	(31)	(4,863)	(5,208)		474	(417)	(128)		(297)
Ending Balance (in shares) at Dec. 31, 2011						331,000,000
Net income (loss)	(723)	(1,188)			527									(723)	(1,188)		527
Other comprehensive income (loss)	(629)	(104)																(629)	(104)
Other comprehensive income (loss)					(524)																(524)
Share-based compensation	14	9			5				14	9		5
Proceeds from exercise of stock options (in shares)	1,327,000					1,000,000
Proceeds from exercise of stock options	17								17
Capital contributions from parent		3			14					3		14
Treasury stock acquisitions	(4)												(4)
Ending Balance at Dec. 31, 2012	$ 481	$ (3,184)	$ 4,347		$ 4,347	$ 3			$ 7,145	$ 3,444		$ 4,167	$ (35)	$ (5,586)	$ (6,396)		$ 1,001	$ (1,046)	$ (232)		$ (821)
Ending Balance (in shares) at Dec. 31, 2012						332,000,000