Consolidated Statements Of Cash Flows (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Statement of Cash Flows [Abstract]
Net Cash Provided by (used for) Operating Activities	$ 1,464	$ 235
Cash Flow from Investing Activities:
Capital expenditures, including aircraft lease deposits	(1,145)	(1,055)
Net (increase) decrease in short-term investments	0	337
Net (increase) decrease in restricted cash and short-term investments	109	24
Proceeds from sale of equipment and property	(57)	9
Net cash used for investing activities	(1,197)	(751)
Cash Flow from Financing Activities:
Payments on long-term debt and capital lease obligations	(990)	(1,233)
Proceeds from:
Issuance of debt	0	1,598
Sale leaseback transactions	853	462
Funds transferred to affiliates, net	94	(175)
Net cash provided by financing activities	(43)	652
Net increase (decrease) in cash	224	136
Cash at beginning of period	280	165
Cash at end of period	$ 504	$ 301