Condensed Consolidated Balance Sheet (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 1,489	$ 1,113
Short-term investments	1,904	1,857
Accounts and other receivables	514	332
Inventories of parts and supplies, at cost	461	469
Deferred income taxes	287	246
Prepaid expenses and other current assets	209	210
Total current assets	4,864	4,227
Property and equipment, at cost:
Flight equipment	16,707	16,367
Ground property and equipment	2,883	2,714
Deposits on flight equipment purchase contracts	633	416
Property and equipment, at cost	20,223	19,497
Less allowance for depreciation and amortization	7,059	6,731
Property and equipment, net	13,164	12,766
Goodwill	970	970
Other assets	384	633
Total assets	19,382	18,596
Current liabilities:
Accounts payable	1,232	1,107
Accrued liabilities	1,207	1,102
Air traffic liability	3,077	2,170
Current maturities of long-term debt	263	271
Total current liabilities	5,779	4,650
Long-term debt less current maturities	2,671	2,883
Deferred income taxes	2,883	2,884
Deferred gains from sale and leaseback of aircraft	57	63
Other noncurrent liabilities	1,211	1,124
Stockholders' equity:
Common stock	808	808
Capital in excess of par value	1,201	1,210
Retained earnings	6,015	5,768
Accumulated other comprehensive loss	(248)	(119)
Treasury stock, at cost	(995)	(675)
Total stockholders' equity	6,781	6,992
Total liabilities and stockholders' equity	$ 19,382	$ 18,596