Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Assets
Cash and cash equivalents	$ 690	$ 956
Accounts receivable – net	955	945
Materials and supplies	222	257
Other current assets	282	133
Total current assets	2,149	2,291
Investments	2,981	2,777
Properties less accumulated depreciation of $11,909 and $11,737 respectively	30,330	29,751
Other assets	251	73
Total assets	35,711	34,892
Liabilities and stockholders’ equity
Accounts payable	1,401	1,215
Short-term debt	100	100
Income and other taxes	211	245
Other current liabilities	233	229
Current maturities of long-term debt	600	550
Total current liabilities	2,545	2,339
Long-term debt	9,136	9,562
Other liabilities	1,347	1,442
Deferred income taxes	6,324	9,140
Total liabilities	19,352	22,483
Stockholders’ equity:
Common stock $1.00 per share par value, 1,350,000,000 shares authorized; outstanding 284,157,187 and 290,417,610 shares, respectively, net of treasury shares	285	292
Additional paid-in capital	2,254	2,179
Accumulated other comprehensive loss	(356)	(487)
Retained income	14,176	10,425
Total stockholders’ equity	16,359	12,409
Total liabilities and stockholders’ equity	$ 35,711	$ 34,892