Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 3,538	$ 4,770
Short-term investments	1,852	1,773
Total unrestricted cash, cash equivalents and short-term investments	5,390	6,543
Restricted cash	50	65
Receivables, less allowance for doubtful accounts	1,679	1,338
Aircraft fuel, spare parts and supplies, less obsolescence allowance	690	695
Deferred income taxes	494	543
Prepaid expenses and other	845	865
Total current assets	9,148	10,049
Operating property and equipment: Owned-
Flight equipment	17,888	17,561
Other property and equipment	3,357	3,269
Operating property and equipment - owned, gross	21,245	20,830
Less - Accumulated depreciation and amortization	(5,305)	(5,006)
Operating property and equipment - owned, net	15,940	15,824
Purchase deposits for flight equipment	534	462
Capital leases-
Flight equipment	1,475	1,484
Other property and equipment	235	235
Operating property and equipment - capital leases, gross	1,710	1,719
Less - Accumulated amortization	(747)	(713)
Operating property and equipment - capital leases, net	963	1,006
Total property, plant, and equipment, net	17,437	17,292
Other assets:
Goodwill	4,523	4,523
Intangibles, less accumulated amortization	4,561	4,597
Restricted cash	385	382
Other, net	788	785
Other assets total	10,257	10,287
Total assets	36,842	37,628
Current liabilities:
Advance ticket sales	4,633	3,360
Frequent flyer deferred revenue	2,312	2,364
Accounts payable	2,293	2,312
Accrued salaries and benefits	1,455	1,763
Current maturities of long-term debt	1,079	1,812
Current maturities of capital leases	121	122
Other	999	1,085
Total current liabilities	12,892	12,818
Long-term debt	10,182	10,440
Long-term obligations under capital leases	765	792
Other liabilities and deferred credits:
Frequent flyer deferred revenue	2,755	2,756
Postretirement benefit liability	2,632	2,614
Pension liability	2,385	2,400
Advanced purchase of miles	1,488	1,537
Deferred income taxes	1,485	1,543
Lease fair value adjustment, net	836	881
Other	1,328	1,366
Total non-current liabilities	12,909	13,097
Commitments and contingencies
Stockholder's equity:
Preferred stock
Common stock	3	3
Additional capital invested	7,159	7,145
Accumulated deficit	(6,003)	(5,586)
Stock held in treasury, at cost	(38)	(35)
Accumulated other comprehensive loss	(1,027)	(1,046)
Total stockholders' equity	94	481
Total liabilities and stockholders' equity (deficit)	36,842	37,628
United Airlines, Inc.
Current assets:
Cash and cash equivalents	3,532	4,765
Short-term investments	1,852	1,773
Total unrestricted cash, cash equivalents and short-term investments	5,384	6,538
Restricted cash	50	65
Receivables from related parties	229	226
Receivables, less allowance for doubtful accounts	1,679	1,338
Aircraft fuel, spare parts and supplies, less obsolescence allowance	690	695
Deferred income taxes	499	546
Prepaid expenses and other	841	841
Total current assets	9,372	10,249
Operating property and equipment: Owned-
Flight equipment	17,888	17,561
Other property and equipment	3,357	3,269
Operating property and equipment - owned, gross	21,245	20,830
Less - Accumulated depreciation and amortization	(5,305)	(5,006)
Operating property and equipment - owned, net	15,940	15,824
Purchase deposits for flight equipment	534	462
Capital leases-
Flight equipment	1,475	1,484
Other property and equipment	235	235
Operating property and equipment - capital leases, gross	1,710	1,719
Less - Accumulated amortization	(747)	(713)
Operating property and equipment - capital leases, net	963	1,006
Total property, plant, and equipment, net	17,437	17,292
Other assets:
Goodwill	4,523	4,523
Intangibles, less accumulated amortization	4,561	4,597
Restricted cash	385	382
Other, net	1,200	1,052
Other assets total	10,669	10,554
Total assets	37,478	38,095
Current liabilities:
Advance ticket sales	4,633	3,360
Frequent flyer deferred revenue	2,312	2,364
Accounts payable	2,296	2,316
Accrued salaries and benefits	1,455	1,763
Current maturities of long-term debt	1,079	1,812
Current maturities of capital leases	121	122
Payables to related parties	73	75
Other	1,073	1,140
Total current liabilities	13,042	12,952
Long-term debt	9,783	10,038
Long-term obligations under capital leases	765	792
Other liabilities and deferred credits:
Frequent flyer deferred revenue	2,755	2,756
Postretirement benefit liability	2,632	2,614
Pension liability	2,385	2,400
Advanced purchase of miles	1,488	1,537
Deferred income taxes	1,415	1,470
Lease fair value adjustment, net	836	881
Other	1,537	1,494
Total non-current liabilities	13,048	13,152
Commitments and contingencies
Stockholder's equity:
Additional capital invested	7,625	7,611
Accumulated deficit	(5,758)	(5,397)
Accumulated other comprehensive loss	(1,027)	(1,053)
Total stockholders' equity	840	1,161
Total liabilities and stockholders' equity (deficit)	$ 37,478	$ 38,095