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	$ 1,567	$ 346
Cash Flow from Investing Activities:
Capital expenditures, including aircraft lease deposits	(1,153)	(1,234)
Net (increase) decrease in short-term investments	0	336
Net (increase) decrease in restricted cash and short-term investments	(109)	(24)
Proceeds from sale of equipment and property	58	(8)
Net cash used for investing activities	(1,204)	(930)
Cash Flow from Financing Activities:
Payments on long-term debt and capital lease obligations	(991)	(1,527)
Proceeds from:
Issuance of debt	0	1,784
Sale leaseback transactions	853	463
Other	0	0
Net cash provided by financing activities	(138)	720
Net increase (decrease) in cash	225	136
Cash at beginning of period	283	168
Cash at end of period	$ 508	$ 304