Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Cash Flows from Operating Activities
Net Income	$ 1,075,278	$ 970,425
Items Not Requiring (Providing) Cash
Depreciation, Depletion and Amortization	2,383,359	1,822,854
Impairments	250,239	531,413
Stock-Based Compensation Expenses	101,337	95,057
Deferred Income Taxes	385,878	499,279
Gains on Asset Dispositions, Net	(248,134)	(442,981)
Other, Net	(10,266)	2,270
Dry Hole Costs	13,005	47,231
Mark-to-Market Commodity Derivative Contracts
Total Gains	(327,328)	(480,539)
Realized Gains	555,946	83,765
Excess Tax Benefits from Stock-Based Compensation	(49,426)	0
Other, Net	12,675	21,052
Changes in Components of Working Capital and Other Assets and Liabilities
Accounts Receivable	(112,174)	(128,965)
Inventories	(154,766)	(167,611)
Accounts Payable	83,682	245,385
Accrued Taxes Payable	42,791	101,239
Other Assets	(120,085)	(28,600)
Other Liabilities	39,871	37,022
Changes in Components of Working Capital Associated with Investing and Financing Activities	87,708	133,227
Net Cash Provided by Operating Activities	4,009,590	3,341,523
Investing Cash Flows
Additions to Oil and Gas Properties	(5,326,884)	(4,665,535)
Additions to Other Property, Plant and Equipment	(477,351)	(502,112)
Proceeds from Sales of Assets	1,213,550	1,294,627
Changes in Components of Working Capital Associated with Investing Activities	(87,654)	(133,512)
Net Cash Used in Investing Activities	(4,678,339)	(4,006,532)
Financing Cash Flows
Common Stock Sold	0	1,388,270
Long-Term Debt Borrowings	1,234,138	0
Dividends Paid	(134,412)	(124,133)
Excess Tax Benefits from Stock-Based Compensation	49,426	0
Treasury Stock Purchased	(44,799)	(21,357)
Proceeds from Stock Options Exercised and Employee Stock Purchase Plan	59,714	26,887
Debt Issuance Costs	(1,771)	0
Repayment of Capital Lease Obligation	(1,407)	0
Other, Net	(54)	285
Net Cash Provided by Financing Activities	1,160,835	1,269,952
Effect of Exchange Rate Changes on Cash	4,811	(7,068)
Increase in Cash and Cash Equivalents	496,897	597,875
Cash and Cash Equivalents at Beginning of Period	615,726	788,853
Cash and Cash Equivalents at End of Period	$ 1,112,623	$ 1,386,728