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COMMITMENTS AND CONTINGENCIES - Additional Information (Detail) (USD $)	6 Months Ended							1 Months Ended						1 Months Ended		6 Months Ended
	Jun. 30, 2012 Employee	Jun. 30, 2012 United Airlines Inc	Jun. 30, 2012 United Airlines Inc Capital Addition Purchase Commitments AirCraft	Jun. 30, 2012 United Airlines Inc Capital Addition Purchase Commitments Boeing 787 AirCraft	Jun. 30, 2012 United Airlines Inc Capital Addition Purchase Commitments Airbus A350XWB AirCraft	Jul. 12, 2012 United Airlines Inc Subsequent Event Capital Addition Purchase Commitments	Jul. 12, 2012 United Airlines Inc Subsequent Event Capital Addition Purchase Commitments Boeing 737 AirCraft	Jul. 12, 2012 United Airlines Inc Subsequent Event Capital Addition Purchase Commitments Aircraft	Jun. 30, 2012 Continental Airlines Inc	Jun. 30, 2012 Continental Airlines Inc Capital Addition Purchase Commitments AirCraft	Jun. 30, 2012 Continental Airlines Inc Capital Addition Purchase Commitments Boeing 737 AirCraft	Jun. 30, 2012 Continental Airlines Inc Capital Addition Purchase Commitments Boeing 787 AirCraft	Jul. 12, 2012 Continental Airlines Inc Subsequent Event Capital Addition Purchase Commitments	Nov. 30, 2011 United Continental Holdings Inc Year	May 31, 2011 United Continental Holdings Inc	Jun. 30, 2012 United Continental Holdings Inc	Jul. 12, 2012 United Continental Holdings Inc Subsequent Event Capital Addition Purchase Commitments Boeing 737 AirCraft	Jun. 30, 2012 United Air Lines Inc and Continental Airline Inc	Jun. 30, 2012 Floating Rate Debt United Airlines Inc	Jun. 30, 2012 Floating Rate Debt Continental Airlines Inc	Jun. 30, 2012 Floating Rate Debt United Continental Holdings Inc	Jun. 30, 2012 Fixed Rate Debt United Airlines Inc	Jun. 30, 2012 Fixed Rate Debt Continental Airlines Inc	Jun. 30, 2012 Fixed Rate Debt United Continental Holdings Inc	Jun. 30, 2012 Loans And Leases From Non U S Entities United Airlines Inc	Jun. 30, 2012 Loans And Leases From Non U S Entities Continental Airlines Inc	Jun. 30, 2012 Loans And Leases From Non U S Entities United Continental Holdings Inc	Jun. 30, 2012 Minimum United Airlines Inc Capital Addition Purchase Commitments	Jul. 12, 2012 Minimum United Airlines Inc Subsequent Event Capital Addition Purchase Commitments Boeing 737	Jun. 30, 2012 Minimum Continental Airlines Inc Capital Addition Purchase Commitments	Jul. 12, 2012 Minimum United Continental Holdings Inc Subsequent Event Capital Addition Purchase Commitments Boeing 737	Jun. 30, 2012 Maximum United Airlines Inc Capital Addition Purchase Commitments	Jul. 12, 2012 Maximum United Airlines Inc Subsequent Event Capital Addition Purchase Commitments Boeing 737	Jun. 30, 2012 Maximum Continental Airlines Inc Capital Addition Purchase Commitments	Jun. 30, 2012 Maximum United Continental Holdings Inc Year	Jul. 12, 2012 Maximum United Continental Holdings Inc Subsequent Event Capital Addition Purchase Commitments Boeing 737	Jun. 30, 2012 Bonds Minimum United Air Lines Inc and Continental Airline Inc	Jun. 30, 2012 Bonds Maximum United Air Lines Inc and Continental Airline Inc
Commitments and Contingencies [Line Items]
Number of new aircraft committed to purchase			100				50			72	47	25					100
Number of new aircraft under purchase rights and options			152				60			89							100
Number of aircraft expected to be delivered				25	25		50				9	5					100
New aircraft, scheduled delivery date																												2013	2013	2012	2013	2019	2022	2016		2022
Lease expiration period								5 years
New aircraft, scheduled delivery date																														Jul. 01, 2012				Dec. 31, 2012
Number of aircraft under financing arrangement expected to be delivered											5	4
New aircraft, scheduled delivery date																														2012-07				2012-12
Percentage of lease rates of orders allocated to each subsidiary						50.00%							50.00%
Reserve required under combined credit card processing agreement																		$ 25,000,000
Expected advanced ticket sales									0
Guarantor obligations, maximum exposure		270,000,000							1,700,000,000
Operating leases obligations		270,000,000							1,500,000,000							1,800,000,000
Capital leases obligations									190,000,000
Debt instrument, maturity year																																					2015	2033
Debt instrument principal amount																			2,000,000,000	498,000,000	2,500,000,000	195,000,000	181,000,000	376,000,000	2,200,000,000	595,000,000	2,800,000,000
Debt instrument, remaining terms (years)																																			10
Terminal improvement project amount															1,000,000,000
Special facilities revenue bonds														113,000,000
Estimated construction cost														100,000,000
Project demand period that determines construction of the remaining phases, minimum years														7
Project demand period that determines construction of the remaining phases, maximum years														10
Commitment capacity available																$ 500,000,000
Number of employees	88,000
Percentage of employees represented by various U.S. labor organizations	80.00%