Consolidated Statements of Income and Comprehensive Income - USD ($) shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Operating Revenues and Other
Total	$ 2,245,484,000	$ 4,303,455,000	$ 8,066,550,000	$ 13,059,727,000
Operating Expenses
Lease and Well	227,473,000	348,883,000	802,478,000	1,032,455,000
Transportation Costs	180,257,000	199,365,000	540,281,000	549,988,000
Gathering and Processing Costs	114,790,000	127,549,000	340,039,000	351,487,000
Exploration Costs	38,413,000	34,540,000	105,373,000	103,386,000
Dry Hole Costs	12,604,000	24,138,000	13,063,000	28,001,000
Impairments	78,990,000	105,275,000	1,957,340,000	289,761,000
Marketing Costs	521,351,000	1,343,293,000	2,074,788,000	4,114,265,000
Depreciation, Depletion and Amortization	823,050,000	953,597,000	2,529,789,000	2,790,496,000
General and Administrative	124,460,000	135,758,000	370,588,000	364,210,000
Taxes Other Than Income	126,810,000	203,098,000	364,489,000	600,418,000
Total	2,248,198,000	3,475,496,000	9,098,228,000	10,224,467,000
Operating Income (Loss)	(2,714,000)	827,959,000	(1,031,678,000)	2,835,260,000
Other Income, Net	3,401,000	9,118,000	17,009,000	23,233,000
Income (Loss) Before Interest Expense and Income Taxes	687,000	837,077,000	(1,014,669,000)	2,858,493,000
Interest Expense
Interest Expense, Net	53,242,000	39,620,000	152,145,000	144,434,000
Income (Loss) Before Income Taxes	(52,555,000)	797,457,000	(1,166,814,000)	2,714,059,000
Income Tax Provision (Benefit)	(10,088,000)	182,335,000	(224,776,000)	615,670,000
Net Income (Loss)	$ (42,467,000)	$ 615,122,000	$ (942,038,000)	$ 2,098,389,000
Net Income (Loss) Per Share
Basic	$ (0.07)	$ 1.06	$ (1.63)	$ 3.63
Diluted	$ (0.07)	$ 1.06	$ (1.63)	$ 3.61
Average Number of Common Shares
Basic	579,055	577,839	578,740	577,498
Diluted	579,055	581,271	578,740	581,190
Other Comprehensive Income (Loss)
Foreign Currency Translation Adjustments	$ (1,807,000)	$ 833,000	$ (3,297,000)	$ (2,616,000)
Other, Net of Tax	7,000	6,000	19,000	18,000
Other Comprehensive Income (Loss)	(1,800,000)	839,000	(3,278,000)	(2,598,000)
Comprehensive Income (Loss)	(44,267,000)	615,961,000	(945,316,000)	2,095,791,000
Crude Oil and Condensate
Operating Revenues and Other
Revenues	1,394,622,000	2,418,989,000	4,074,747,000	7,148,258,000
Natural Gas Liquids
Operating Revenues and Other
Revenues	184,771,000	164,736,000	439,215,000	569,748,000
Natural Gas
Operating Revenues and Other
Revenues	183,790,000	269,625,000	535,250,000	874,489,000
Gains (Losses) on Mark-to-Market Commodity Derivative Contracts
Operating Revenues and Other
Revenues	(3,978,000)	85,902,000	1,075,433,000	242,622,000
Gathering, Processing and Marketing
Operating Revenues and Other
Revenues	538,955,000	1,334,450,000	1,940,387,000	4,121,490,000
Gains (Losses) on Asset Dispositions, Net
Operating Revenues and Other
Revenues	(70,976,000)	(523,000)	(41,283,000)	3,650,000
Other, Net
Operating Revenues and Other
Revenues	$ 18,300,000	$ 30,276,000	$ 42,801,000	$ 99,470,000