Consolidated Balance Sheets (Unaudited) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Assets
Cash and cash equivalents	$ 678	$ 827
Short-term investments	228	283
Accounts receivable, net	991	807
Materials and supplies	201	169
Deferred income taxes	163	145
Other current assets	54	240
Total current assets	2,315	2,471
Investments	2,235	2,193
Properties less accumulated depreciation of $9,217 and $9,262, respectively	23,671	23,231
Other assets	257	304
Total assets	28,478	28,199
Liabilities and stockholders' equity
Accounts payable	1,254	1,181
Short-term debt	0	100
Income and other taxes	160	199
Other current liabilities	284	244
Current maturities of long-term debt	55	358
Total current liabilities	1,753	2,082
Long-term debt	6,931	6,567
Other liabilities	1,795	1,793
Deferred income taxes	7,372	7,088
Total liabilities	17,851	17,530
Stockholders' equity:
Common stock $1.00 per share par value, 1,350,000,000 shares authorized; outstanding 347,773,580 and 357,362,604 shares, respectively, net of treasury shares	349	358
Additional paid-in capital	1,951	1,892
Accumulated other comprehensive loss	(770)	(805)
Retained income	9,097	9,224
Total stockholders' equity	10,627	10,669
Total liabilities and stockholders' equity	$ 28,478	$ 28,199