CONSOLIDATED BALANCE SHEETS (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Current assets
Cash and cash equivalents	$ 1,278,981	$ 535,825
Canadian government securities with maturities greater than 90 days at the date of acquisition	493,705	616,558
Accounts receivable, less allowance for doubtful accounts of $7,945 in 2011 and $7,954 in 2010	1,780,976	1,467,311
Inventories, at lower of cost or market
Crude oil and blend stocks	237,999	147,256
Finished products	195,678	388,162
Materials and supplies	205,023	226,795
Prepaid expenses	113,841	88,241
Deferred income taxes	75,748	80,545
Assets held for sale	78,679	0
Total current assets	4,460,630	3,550,693
Property, plant and equipment, at cost less accumulated depreciation, depletion and amortization of $6,121,765 in 2011 and $6,040,996 in 2010	10,338,783	10,367,847
Goodwill	40,716	42,850
Deferred charges and other assets	184,606	271,853
Assets held for sale	466,347	0
Total assets	15,491,082	14,233,243
Current liabilities
Current maturities of long-term debt	349,975	41
Accounts payable and accrued liabilities	2,792,520	2,572,105
Income taxes payable	321,375	358,764
Total current liabilities	3,463,870	2,930,910
Long-term debt	974,541	939,350
Deferred income taxes	1,230,237	1,212,213
Asset retirement obligations	566,597	555,248
Deferred credits and other liabilities	367,485	395,972
Stockholders' equity
Cumulative Preferred Stock, par $100, authorized 400,000 shares, none issued	0	0
Common Stock, par $1.00, authorized 450,000,000 shares, issued 193,719,102 shares in 2011 and 193,293,526 shares in 2010	193,719	193,294
Capital in excess of par value	799,565	767,762
Retained earnings	7,628,093	6,800,992
Accumulated other comprehensive income	272,115	449,428
Treasury stock, 197,191 shares of Common Stock in 2011 and 457,518 shares of Common Stock in 2010, at cost	(5,140)	(11,926)
Total stockholders' equity	8,888,352	8,199,550
Total liabilities and stockholders' equity	$ 15,491,082	$ 14,233,243