Consolidated Statements of Cash Flows - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash Flows from Operating Activities
Net Income		$ 2,734,910	$ 3,419,040	$ 2,582,579
Items Not Requiring (Providing) Cash
Depreciation, Depletion and Amortization		3,749,704	3,435,408	3,409,387
Impairments		517,896	347,021	479,240
Stock-Based Compensation Expenses		174,738	155,337	133,849
Deferred Income Taxes		631,658	894,156	(1,473,872)
(Gains) Losses on Asset Dispositions, Net		(123,613)	(174,562)	99,096
Other, Net		4,496	7,066	6,546
Dry Hole Costs	[1]	28,001	5,405	4,609
Mark-to-Market Commodity Derivative Contracts
Total (Gains) Losses		(180,275)	165,640	(19,828)
Net Cash Received from (Payments for) Settlements of Commodity Derivative Contracts		231,229	(258,906)	7,438
Other, Net		962	3,108	1,204
Changes in Components of Working Capital and Other Assets and Liabilities
Accounts Receivable		(91,792)	(368,180)	(392,131)
Inventories		90,284	(395,408)	(174,548)
Accounts Payable		168,539	439,347	324,192
Accrued Taxes Payable		40,122	(92,461)	(63,937)
Other Assets		358,001	(125,435)	(658,609)
Other Liabilities		(56,619)	10,949	(89,871)
Changes in Components of Working Capital Associated with Investing and Financing Activities		(115,061)	301,083	89,992
Net Cash Provided by Operating Activities		8,163,180	7,768,608	4,265,336
Investing Cash Flows
Additions to Oil and Gas Properties		(6,151,885)	(5,839,294)	(3,950,918)
Additions to Other Property, Plant and Equipment		(270,641)	(237,181)	(173,324)
Proceeds from Sales of Assets		140,292	227,446	226,768
Payments for (Proceeds from) Other Investing Activities		(10,000)	(19,993)	0
Changes in Components of Working Capital Associated with Investing Activities		115,061	(301,140)	(89,935)
Net Cash Used in Investing Activities		(6,177,173)	(6,170,162)	(3,987,409)
Financing Cash Flows
Long-Term Debt Repayments		(900,000)	(350,000)	(600,000)
Dividends Paid		(588,200)	(438,045)	(386,531)
Treasury Stock Purchased		(25,152)	(63,456)	(63,408)
Proceeds from Stock Options Exercised and Employee Stock Purchase Plan		17,946	20,560	20,840
Debt Issuance Costs		(5,016)	0	0
Repayment of Capital Lease Obligation		(12,899)	(8,219)	(6,555)
Other, Net		0	57	(57)
Net Cash Used in Financing Activities		(1,513,321)	(839,103)	(1,035,711)
Effect of Exchange Rate Changes on Cash		(348)	(37,937)	(7,883)
Increase (Decrease) in Cash and Cash Equivalents		472,338	721,406	(765,667)
Cash and Cash Equivalents at Beginning of Year		1,555,634	834,228	1,599,895
Cash and Cash Equivalents at End of Year		$ 2,027,972	$ 1,555,634	$ 834,228

[1] Excludes gains or losses on the mark-to-market of financial commodity derivative contracts, gains or losses on sales of reserves and related assets, interest charges and general corporate expenses for each of the three years in the period ended December 31, 2019.