Income Taxes (Deferred Tax Assets And Liabilities) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Income Taxes [Abstract]
Postretirement benefits other than pensions	$ 1,074	$ 1,056
Rent expense	325	333
Alternative minimum tax credit carryforwards	367	392
Operating loss carryforwards	2,389	2,271
Pensions	2,341	1,865
Frequent flyer obligation	681	630
Gains from lease transactions	28	55
Other	681	583
Total deferred tax assets	7,886	7,185
Valuation allowance	(4,148)	(2,990)
Net deferred tax assets	3,738	4,195
Accelerated depreciation and amortization	(3,543)	(3,985)
Other	(195)	(185)
Total deferred tax liabilities	(3,738)	(4,170)
Net deferred tax asset	$ 0	$ 25