Consolidated Statements Of Cash Flows (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Statement of Cash Flows [Abstract]
Net Cash Provided by (used for) Operating Activities	$ 1,722	$ 653
Cash Flow from Investing Activities:
Capital expenditures, including aircraft lease deposits	(733)	(748)
Net (increase) decrease in short-term investments	(890)	(530)
Net (increase) decrease in restricted cash and short-term investments	(34)	(7)
Proceeds from sale of equipment and property	57	(13)
Net cash used for investing activities	(1,600)	(1,298)
Cash Flow from Financing Activities:
Payments on long-term debt and capital lease obligations	(602)	(1,184)
Proceeds from:
Issuance of debt	0	1,717
Sale leaseback transactions	568	262
Other	0	0
Net cash provided by financing activities	(34)	795
Net increase (decrease) in cash	88	150
Cash at beginning of period	283	168
Cash at end of period	$ 371	$ 318