Consolidated Statements of Income and Comprehensive Income - USD ($) shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Operating Revenues and Other
Total	$ 1,103,374,000	$ 4,697,630,000	$ 5,821,066,000	$ 8,756,272,000
Operating Expenses
Lease and Well	245,346,000	347,281,000	575,005,000	683,572,000
Transportation Costs	151,728,000	174,101,000	360,024,000	350,623,000
Gathering and Processing Costs	96,767,000	112,643,000	225,249,000	223,938,000
Exploration Costs	27,283,000	32,522,000	66,960,000	68,846,000
Dry Hole Costs	87,000	3,769,000	459,000	3,863,000
Impairments	305,415,000	112,130,000	1,878,350,000	184,486,000
Marketing Costs	444,444,000	1,500,915,000	1,553,437,000	2,770,972,000
Depreciation, Depletion and Amortization	706,679,000	957,304,000	1,706,739,000	1,836,899,000
General and Administrative	131,855,000	121,780,000	246,128,000	228,452,000
Taxes Other Than Income	80,319,000	204,414,000	237,679,000	397,320,000
Total	2,189,923,000	3,566,859,000	6,850,030,000	6,748,971,000
Operating Income (Loss)	(1,086,549,000)	1,130,771,000	(1,028,964,000)	2,007,301,000
Other Income (Expense), Net	(4,500,000)	8,503,000	13,608,000	14,115,000
Income (Loss) Before Interest Expense and Income Taxes	(1,091,049,000)	1,139,274,000	(1,015,356,000)	2,021,416,000
Interest Expense
Interest Expense, Net	54,213,000	49,908,000	98,903,000	104,814,000
Income (Loss) Before Income Taxes	(1,145,262,000)	1,089,366,000	(1,114,259,000)	1,916,602,000
Income Tax Provision (Benefit)	(235,878,000)	241,525,000	(214,688,000)	433,335,000
Net Income (Loss)	$ (909,384,000)	$ 847,841,000	$ (899,571,000)	$ 1,483,267,000
Net Income (Loss) Per Share
Basic	$ (1.57)	$ 1.47	$ (1.55)	$ 2.57
Diluted	$ (1.57)	$ 1.46	$ (1.55)	$ 2.56
Average Number of Common Shares
Basic	578,719	577,460	578,581	577,333
Diluted	578,719	580,247	578,581	580,204
Other Comprehensive Income (Loss)
Foreign Currency Translation Adjustments	$ (2,831,000)	$ (1,665,000)	$ (1,490,000)	$ (3,449,000)
Other, Net of Tax	6,000	6,000	12,000	12,000
Other Comprehensive Income (Loss)	(2,825,000)	(1,659,000)	(1,478,000)	(3,437,000)
Comprehensive Income (Loss)	(912,209,000)	846,182,000	(901,049,000)	1,479,830,000
Crude Oil and Condensate
Operating Revenues and Other
Revenues	614,627,000	2,528,866,000	2,680,125,000	4,729,269,000
Natural Gas Liquids
Operating Revenues and Other
Revenues	93,909,000	186,374,000	254,444,000	405,012,000
Natural Gas
Operating Revenues and Other
Revenues	141,696,000	269,892,000	351,460,000	604,864,000
Gains (Losses) on Mark-to-Market Commodity Derivative Contracts
Operating Revenues and Other
Revenues	(126,362,000)	177,300,000	1,079,411,000	156,720,000
Gathering, Processing and Marketing
Operating Revenues and Other
Revenues	362,786,000	1,501,386,000	1,401,432,000	2,787,040,000
Gains (Losses) on Asset Dispositions, Net
Operating Revenues and Other
Revenues	13,233,000	8,009,000	29,693,000	4,173,000
Other, Net
Operating Revenues and Other
Revenues	$ 3,485,000	$ 25,803,000	$ 24,501,000	$ 69,194,000