EARNINGS (LOSS) PER SHARE - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
UAL 6% Senior Convertible Notes
Earnings Loss Per Share [Line Items]
Debt Outstanding	$ 652		$ 652
Debt instrument convertible effective interest rate	6.00%	6.00%	6.00%	6.00%
Due date of debt instruments	2031		2031
UAL 8% Contingent Senior Notes
Earnings Loss Per Share [Line Items]
Debt Outstanding	125		125
Debt instrument convertible effective interest rate			8.00%
Obligated to issue an additional Notes	62.5		62.5
Issuance date of additional notes	2013-02		2013-02
UAL 4.5% Senior Limited-Subordination Convertible Notes
Earnings Loss Per Share [Line Items]
Debt Outstanding		726		726
Debt instrument convertible effective interest rate		4.50%
Due date of debt instruments		2021		2021
Repurchased debt		570