Segment Information (Details) - USD ($)		3 Months Ended			6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020		Jun. 30, 2021	Jun. 30, 2020		Dec. 31, 2020
Schedule of Segment Reporting Information By Segment [Abstract]
Operating Revenues and Other		$ 4,139,000,000	$ 1,103,000,000		$ 7,833,000,000	$ 5,821,000,000
Operating Income (Loss)		1,171,000,000	(1,087,000,000)		2,103,000,000	(1,029,000,000)
Other Income (Expense), Net		(2,000,000)	(4,000,000)		(6,000,000)	14,000,000
Interest Expense, Net		(45,000,000)	(54,000,000)		(92,000,000)	(99,000,000)
Income (Loss) Before Income Taxes		1,124,000,000	(1,145,000,000)		2,005,000,000	(1,114,000,000)
Total Assets		36,885,000,000			36,885,000,000			$ 35,805,000,000
United States
Schedule of Segment Reporting Information By Segment [Abstract]
Operating Revenues and Other		3,995,000,000	1,055,000,000		7,601,000,000	5,716,000,000
Operating Income (Loss)	[1]	1,077,000,000	(1,079,000,000)		1,967,000,000	(974,000,000)
Total Assets		36,057,000,000			36,057,000,000			35,048,000,000
Pretax Impairment Charges for Proved Oil and Gas Properties and Other Property, Plant and Equipment			6,000,000			1,462,000,000
Pretax Impairment Changes For Other Assets			219,000,000			219,000,000
Trinidad
Schedule of Segment Reporting Information By Segment [Abstract]
Operating Revenues and Other		81,000,000	34,000,000		157,000,000	76,000,000
Operating Income (Loss)		41,000,000	10,000,000		84,000,000	23,000,000
Total Assets		580,000,000			580,000,000			546,000,000
Other International
Schedule of Segment Reporting Information By Segment [Abstract]
Operating Revenues and Other	[2]	63,000,000	14,000,000		75,000,000	29,000,000
Operating Income (Loss)	[2]	53,000,000	(18,000,000)	[3]	52,000,000	(78,000,000)	[3]
Total Assets	[4]	$ 248,000,000			$ 248,000,000			$ 211,000,000
Pretax Impairment Charges for Proved Oil and Gas Properties and Other Property, Plant and Equipment			$ 19,000,000			$ 79,000,000

[1] EOG recorded pretax impairment charges of $6 million and $1,462 million for the three and six months ended June 30, 2020, respectively, for proved oil and gas properties, leasehold costs and other assets due to the decline in commodity prices. See Note 11. In addition, EOG recorded pretax impairment charges of $219 million for the three and six months ended June 30, 2020, for sand and crude-by-rail assets.

[2] Other International primarily consists of EOG's China and Canada operations. The China operations were sold in the second quarter of 2021. EOG began an exploration program in Oman in the third quarter of 2020.

[3] EOG recorded pretax impairment charges of $19 million for the three months ended June 30, 2020, and $79 million for the six months ended June 30, 2020, for proved oil and gas properties and firm commitment contracts related to its decision to exit the Horn River Basin in British Columbia, Canada.

[4] Other International primarily consists of EOG's China and Canada operations. The China operations were sold in the second quarter of 2021. EOG began an exploration program in Oman in the third quarter of 2020.