Business Segment Information (Details) - USD ($) $ in Thousands		3 Months Ended													12 Months Ended
		Dec. 31, 2017		Sep. 30, 2017		Jun. 30, 2017		Mar. 31, 2017		Dec. 31, 2016		Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017		Dec. 31, 2016		Dec. 31, 2015
Schedule of Segment Reporting Information By Segment [Abstract]
Crude Oil and Condensate															$ 6,256,396		$ 4,317,341		$ 4,934,562
Natural Gas Liquids															729,561		437,250		407,658
Natural Gas															921,934		742,152		1,061,038
Gains (Losses) on Mark-to-Market Commodity Derivative Contracts															19,828		(99,608)		61,924
Gathering, Processing and Marketing															3,298,087		1,966,259		2,253,135
Gains (Losses) on Asset Dispositions, Net															(99,096)		205,835		(8,798)
Other, Net	[1]														81,610		81,403		47,909
Net Operating Revenues and Other		$ 3,340,439		$ 2,644,844		$ 2,612,472		$ 2,610,565		$ 2,402,039		$ 2,118,504	$ 1,775,740	$ 1,354,349	11,208,320		7,650,632		8,757,428
Depreciation, Depletion and Amortization															3,409,387		3,553,417		3,313,644
Operating Income (Loss)		475,912		214,836		127,908		107,746		(105,487)		(193,480)	(288,173)	(638,141)	926,402		(1,225,281)		(6,686,079)
Interest Income															7,713		2,619		3,469
Other Income															1,439
Other Expense																	(53,162)		(1,553)
Net Interest Expense															274,372		281,681		237,393
Income (Loss) Before Income Taxes															661,182		(1,557,505)		(6,921,556)
Income Tax Provision (Benefit)		(2,017,115)	[2]	$ 45,439	[2]	$ 39,414	[2]	$ 10,865	[2]	(51,658)		$ (82,250)	$ (87,719)	$ (239,192)	(1,921,397)		(460,819)		(2,397,041)
Additions to Oil and Gas Properties, Excluding Dry Hole Costs															4,228,228		6,329,369		4,710,404
Total Property, Plant and Equipment, Net		25,665,037								25,707,078					25,665,037		25,707,078		24,210,721
Total Assets		29,833,078								29,299,201	[3]				29,833,078		29,299,201	[3]	26,834,908	[4]
Reclassification to Deferred Tax Assets		17,506								16,140					17,506		16,140
United States
Schedule of Segment Reporting Information By Segment [Abstract]
Crude Oil and Condensate															6,225,711		4,265,036		4,917,731
Natural Gas Liquids															729,545		437,238		407,570
Natural Gas															615,512		475,715		637,452
Gains (Losses) on Mark-to-Market Commodity Derivative Contracts															19,828		(99,608)		61,924
Gathering, Processing and Marketing															3,298,098		1,967,390		2,254,477
Gains (Losses) on Asset Dispositions, Net															(98,233)		196,043		(12,176)
Other, Net															81,610		81,386		47,464
Net Operating Revenues and Other															10,872,071	[5]	7,323,200	[6]	8,314,442	[7]
Depreciation, Depletion and Amortization															3,269,196		3,365,390		3,139,863
Operating Income (Loss)															933,571		(1,192,338)		(6,566,282)
Interest Income															3,223		358		1,913
Other Income																			6,461
Other Expense															(9,659)		(15,703)
Net Interest Expense															303,941		298,125		274,606
Income (Loss) Before Income Taxes															623,194		(1,505,808)		(6,832,514)
Income Tax Provision (Benefit)															(1,964,343)		(516,180)		(2,463,213)
Additions to Oil and Gas Properties, Excluding Dry Hole Costs															4,067,359		6,223,228		4,495,730
Total Property, Plant and Equipment, Net		25,125,427								25,221,517					25,125,427		25,221,517		23,593,995
Total Assets		28,312,599								27,746,851	[3]				28,312,599		27,746,851	[3]	25,211,572	[4]
Amount of sales with a single significant purchaser in the United States segment															1,500,000		1,200,000		1,700,000
Amount of sales with a second significant purchaser in the United States segment.															1,300,000		1,100,000		1,400,000
Amount of sales with a third significant purchaser in the United States segment																	1,000,000
Reclassification to Deferred Tax Assets										160,000							160,000		136,000
Trinidad
Schedule of Segment Reporting Information By Segment [Abstract]
Crude Oil and Condensate															13,572		9,600		13,122
Natural Gas Liquids															0		0		0
Natural Gas															271,101		234,108		368,639
Gains (Losses) on Mark-to-Market Commodity Derivative Contracts															0		0		0
Gathering, Processing and Marketing															(11)		(1,131)		(1,342)
Gains (Losses) on Asset Dispositions, Net															(8)		(145)		393
Other, Net															59		(8)		(3)
Net Operating Revenues and Other															284,713		242,424		380,809
Depreciation, Depletion and Amortization															115,321		145,591		154,853
Operating Income (Loss)															101,010		46,473		175,658
Interest Income															2,201		932		389
Other Income															3,337		2,667		8,780
Net Interest Expense															0		0		1,400
Income (Loss) Before Income Taxes															106,548		50,072		183,427
Income Tax Provision (Benefit)															38,798		64,281		63,502
Additions to Oil and Gas Properties, Excluding Dry Hole Costs															145,937		75,407		102,358
Total Property, Plant and Equipment, Net		313,357								274,850					313,357		274,850		350,766
Total Assets		974,477								889,253					974,477		889,253		886,826
Other International
Schedule of Segment Reporting Information By Segment [Abstract]
Crude Oil and Condensate	[8]														17,113		42,705		3,709
Natural Gas Liquids	[8]														16		12		88
Natural Gas	[8]														35,321		32,329		54,947
Gains (Losses) on Mark-to-Market Commodity Derivative Contracts	[8]														0		0		0
Gathering, Processing and Marketing	[8]														0		0		0
Gains (Losses) on Asset Dispositions, Net	[8]														(855)		9,937		2,985
Other, Net	[8]														(59)		25		448
Net Operating Revenues and Other	[8]														51,536		85,008		62,177
Depreciation, Depletion and Amortization	[8]														24,870		42,436		18,928
Operating Income (Loss)	[8]														(108,179)		(79,416)		(295,455)
Interest Income	[8]														2,289		1,329		1,167
Other Income	[8]														7,761
Other Expense	[8]																(40,126)		(16,794)
Net Interest Expense	[8]														(29,569)		(16,444)		(38,613)
Income (Loss) Before Income Taxes	[8]														(68,560)		(101,769)		(272,469)
Income Tax Provision (Benefit)	[8]														4,148		(8,920)		2,670
Additions to Oil and Gas Properties, Excluding Dry Hole Costs	[8]														14,932		30,734		112,316
Total Property, Plant and Equipment, Net	[8]	226,253								210,711					226,253		210,711		265,960
Total Assets	[8]	$ 546,002								$ 663,097					$ 546,002		$ 663,097		$ 736,510

[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, 2017.

[2] Includes an income tax benefit of approximately $2.2 billion for the quarter ended December 31, 2017, primarily due to the enactment of the Tax Cuts and Jobs Act in December 2017. See Note 6 to the Consolidated Financial Statements.

[3] EOG made a reclassification of $160 million from deferred tax liabilities to deferred tax assets for the year ended December 31, 2016, for the United States segment and in total.

[4] EOG made a reclassification of $136 million from deferred tax liabilities to deferred tax assets for the year ended December 31, 2015, for the United States segment and in total.

[5] EOG had sales activity with two significant purchasers in 2017, one totaling $1.5 billion and the other totaling $1.3 billion of consolidated Net Operating Revenues and Other in the United States segment.

[6] EOG had sales activity with three significant purchasers in 2016, one totaling $1.2 billion, one totaling $1.1 billion and one totaling $1.0 billion of consolidated Net Operating Revenues and Other in the United States segment.

[7] EOG had sales activity with two significant purchasers in 2015, one totaling $1.7 billion and the other totaling $1.4 billion of consolidated Net Operating Revenues and Other in the United States segment.

[8] Other International primarily consists of EOG's United Kingdom, China, Canada and Argentina operations. The Argentina operations were sold in the third quarter of 2016.