Condensed Statements Of Consolidated Cash Flows (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Cash Flows from Operating Activities:
Net loss	$ (448)	$ (213)
Adjustments to reconcile net loss to net cash provided (used) by operating activities -
Increase in advance ticket sales	1,319	1,326
Decrease in other liabilities	(470)	(235)
Increase in receivables	(427)	(379)
Depreciation and amortization	380	388
Increase in other current assets	(288)	(190)
Increase in accounts payable	230	98
Increase (decrease) in frequent flyer deferred revenue and advanced purchase of miles	(136)	38
Debt and lease discount amortization	(70)	(44)
Special charges, non-cash portion	12	4
Increase (decrease) in fuel hedge collateral	(1)	178
Other, net	23	34
Net cash provided by operating activities	124	1,005
Cash Flows from Investing Activities:
Capital expenditures	(266)	(205)
Increase in short-term and other investments, net	(148)	(107)
Proceeds from sale of property and equipment	89	39
Aircraft purchase deposits paid, net	(35)	(38)
(Increase) decrease in restricted cash, net	(2)	(9)
Net cash used in investing activities	(362)	(320)
Cash Flows from Financing Activities:
Payments of long-term debt	(479)	(528)
Proceeds from issuance of long-term debt	86	32
Principal payments under capital leases	(23)	(125)
Other, net	14	32
Net cash used in financing activities	(402)	(589)
Net increase (decrease) in cash and cash equivalents during the period	(640)	96
Cash and cash equivalents at beginning of the period	6,246	8,069
Cash and cash equivalents at end of the period	5,606	8,165
Investing and Financing Activities Not Affecting Cash:
Property and equipment acquired through the issuance of debt	136	64
United Airlines Inc [Member]
Cash Flows from Operating Activities:
Net loss	(423)	(160)
Adjustments to reconcile net loss to net cash provided (used) by operating activities -
Increase in advance ticket sales	1,759	736
Decrease in other liabilities	(256)	(119)
Increase in receivables	(805)	(159)
Depreciation and amortization	231	227
Increase in other current assets	(157)	(60)
Increase in accounts payable	281	148
Increase (decrease) in frequent flyer deferred revenue and advanced purchase of miles	(98)	(41)
Debt and lease discount amortization	9	22
Special charges, non-cash portion		6
Increase in receivables from related parties	(427)	(20)
Increase (decrease) in fuel hedge collateral	(1)	178
Increase (decrease) in payables to related parties	41	(2)
Other, net	14	30
Net cash provided by operating activities	168	786
Cash Flows from Investing Activities:
Capital expenditures	(113)	(125)
Increase in short-term and other investments, net	(59)	2
Proceeds from sale of property and equipment	56	1
Aircraft purchase deposits paid, net	(3)	(3)
(Increase) decrease in restricted cash, net	(2)	(10)
Net cash used in investing activities	(121)	(135)
Cash Flows from Financing Activities:
Payments of long-term debt	(147)	(397)
Principal payments under capital leases	(23)	(125)
Other, net	3	12
Net cash used in financing activities	(167)	(510)
Net increase (decrease) in cash and cash equivalents during the period	(120)	141
Cash and cash equivalents at beginning of the period	3,458	4,665
Cash and cash equivalents at end of the period	3,338	4,806
Investing and Financing Activities Not Affecting Cash:
Transfer of frequent flyer liability and advanced purchase of miles from subsidiary	2,387
Continental Airlines Inc [Member]
Cash Flows from Operating Activities:
Net loss	(8)	(57)
Adjustments to reconcile net loss to net cash provided (used) by operating activities -
Increase in advance ticket sales	(440)	589
Decrease in other liabilities	(207)	(127)
Increase in receivables	378	(220)
Depreciation and amortization	149	161
Increase in other current assets	(171)	(108)
Increase in accounts payable	(51)	(52)
Increase (decrease) in frequent flyer deferred revenue and advanced purchase of miles	(39)	79
Debt and lease discount amortization	(79)	(65)
Special charges, non-cash portion	11	(2)
Increase in receivables from related parties	(1)	(63)
Increase (decrease) in payables to related parties	386	79
Other, net	27	4
Net cash provided by operating activities	(45)	218
Cash Flows from Investing Activities:
Capital expenditures	(153)	(80)
Increase in short-term and other investments, net	(88)	(109)
Proceeds from sale of property and equipment	33	38
Aircraft purchase deposits paid, net	(32)	(35)
(Increase) decrease in restricted cash, net		2
Net cash used in investing activities	(240)	(184)
Cash Flows from Financing Activities:
Payments of long-term debt	(331)	(131)
Proceeds from issuance of long-term debt	86	32
Other, net	10	20
Net cash used in financing activities	(235)	(79)
Net increase (decrease) in cash and cash equivalents during the period	(520)	(45)
Cash and cash equivalents at beginning of the period	2,782	3,398
Cash and cash equivalents at end of the period	2,262	3,353
Investing and Financing Activities Not Affecting Cash:
Transfer of frequent flyer liability and advanced purchase of miles from subsidiary	2,387
Property and equipment acquired through the issuance of debt	$ 136	$ 64