CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Current assets
Cash and cash equivalents	$ 947,316	$ 513,873	[1]
Canadian government securities with maturities greater than 90 days at the date of acquisition	115,603	532,093
Accounts receivable, less allowance for doubtful accounts of $6,697 in 2012 and $7,892 in 2011	1,853,364	1,554,184
Inventories, at lower of cost or market
Crude oil and blend stocks	226,541	189,320
Finished products	266,307	254,880
Materials and supplies	259,462	222,438
Prepaid expenses	335,831	93,397
Deferred income taxes	89,040	87,486
Assets held for sale	15,119	0
Total current assets	4,108,583	3,447,671
Property, plant and equipment, at cost less accumulated depreciation, depletion and amortization of $8,138,587 in 2012 and $6,861,494 in 2011	13,011,606	10,475,149
Goodwill	43,103	41,863
Deferred charges and other assets	151,183	173,455
Assets held for sale	208,168	0
Total assets	17,522,643	14,138,138
Current liabilities
Current maturities of long-term debt	46	350,005
Accounts payable	2,803,268	1,941,008
Income taxes payable	219,847	201,784
Other taxes payable	172,962	169,535
Other accrued liabilities	162,876	140,024
Deferred income taxes	2,611	22,572
Liabilities associated with assets held for sale	47,471	0
Total current liabilities	3,409,081	2,824,928
Long-term debt	2,245,201	249,553
Deferred income taxes	1,544,336	1,230,111
Asset retirement obligations	724,273	615,545
Deferred credits and other liabilities	516,540	439,604
Liabilities associated with assets held for sale	141,177	0
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 at December 31, 2012 and 2011, issued 194,616,470 shares at December 31, 2012 and 193,909,200 shares at December 31, 2011	194,616	193,909
Capital in excess of par value	873,934	817,974
Retained earnings	7,717,389	7,460,942
Accumulated other comprehensive income	408,901	310,420
Treasury stock	(252,805)	(4,848)
Total stockholders' equity	8,942,035	8,778,397
Total liabilities and stockholders' equity	$ 17,522,643	$ 14,138,138

[1] Reclassified to conform to current presentation.