Employee Benefit Plans (Details)		12 Months Ended
		Dec. 31, 2018 USD ($) $ / shares shares		Dec. 31, 2017 USD ($) $ / shares shares		Dec. 31, 2016 USD ($) $ / shares shares
Stock Options/SARs and Employee Stock Purchase Plan (ESPP) Disclosures [Line Items]
Common Shares Available for Grant		13,700,000
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense | $		$ 20,000,000		$ 32,000,000
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation | $						$ 29,357,000
Performance Units and Performance Stock [Abstract]
Compensation expense related to the company's stock-based compensation plans | $		$ 155,337,000		133,849,000		128,090,000
Stock Options and Sars [Member]
Stock Options/SARs and Employee Stock Purchase Plan (ESPP) Disclosures [Line Items]
Maximum term of stock options and SARs granted		7 years
Share-based Compensation Expense Related To Stock Options, SAR and ESPP Grants | $		$ 60,000,000		56,000,000		57,000,000
Stock Options/SARs Vested or Expected to Vest (in shares)		8,000,000
Weighted average grant price for stock options/SARs vested or expected to vest (per share) | $ / shares		$ 96.43
Intrinsic value of stock options/SARs vested or expected to vest | $		$ 34,600,000
Weighted Average Remaining Contractual Life for Stock Options/SARs Vested or Expected to Vest		4 years 4 months 24 days
Unrecognized compensation expense | $		$ 106,000,000
Weighted average period over which unrecognized compensation expense will be recognized		1 year 8 months 12 days
Intrinsic Value Of Stock Options/SARs Exercised During The Period | $		$ 118,000,000		$ 95,000,000		$ 84,000,000
Weighted Average Fair Value And Valuation Assumptions Used To Value Stock Options/SARs, ESPP, and Performance Units/Stock-Based Compensation [Abstract]
Weighted Average Fair Value of Grants (price per share) | $ / shares		$ 33.46		$ 23.95		$ 25.78
Expected Volatility (in hundredths)		28.23%		28.28%		31.54%
Risk-Free Interest Rate (in hundredths)		2.68%		1.52%		0.78%
Dividend Yield (in hundredths)		0.72%		0.75%		0.76%
Expected Life (in years)		5 years		5 years 1 month		5 years 4 months 24 days
Stock Options and SARs Rollforward [Abstract]
Outstanding at January 1 (in shares)		9,103,000		9,850,000		10,744,000
Granted (in shares)		1,906,000		2,274,000		1,855,000
Exercised (1) (in shares)	[1]	(2,493,000)		(2,574,000)		(2,376,000)
Forfeited (in shares)		(206,000)		(447,000)		(373,000)
Outstanding at December 31 (in shares)		8,310,000		9,103,000		9,850,000
Stock Options/SARs Exercisable at December 31 (in shares)		3,969,000		4,510,000		5,613,000
Stock Options/SARs Exercisable at December 31 (in dollars per share) | $ / shares		$ 85.82		$ 75.76		$ 66.48
Weighted Average Grant Price Stock Option and SARs [Rollfoward]
Outstanding at January 1 (in dollars per share) | $ / shares		83.89		75.53		67.98
Exercised (in dollars per share) | $ / shares	[1]	72.21		61.12		54.56
Granted (in dollars per share) | $ / shares		126.49		96.27		94.82
Forfeited (in dollars per share) | $ / shares		94.43		93.84		87.38
Outstanding at December 31 (in dollars per share) | $ / shares		$ 96.90		83.89		75.53
Summary Information By Grant Price Range For Stock Options And SARs Outstanding And Exercisable At End Of Period [Line Items]
Stock Options and SARs Outstanding		8,310,000
Weighted Average Remaining Life for Outstanding Options and SARs		5 years
Weighted Average Grant Price For Outstanding Options and SARs | $ / shares		$ 96.90
Aggregate Intrinsic Value For Outstanding Options and SARs | $	[2]	$ 35,083
Stock Options and SARs Exercisable		3,969,000
Weighted Average Remaining Life For Exercisable Units		3 years
Weighted Average Grant Price For Exercisable Options and SARs | $ / shares		$ 85.82
Aggregate Intrinsic Value For Exercisable Units | $	[2]	$ 28,993
ESPP [Member]
Stock Options/SARs and Employee Stock Purchase Plan (ESPP) Disclosures [Line Items]
Common Shares Available for Grant		2,500,000
Percentage of fair market value at which employees may purchase company stock via the ESPP		85.00%
Maximum Percentage Of Employee Pay Eligible For Contribution To ESPP Percentage		10.00%
Weighted Average Fair Value And Valuation Assumptions Used To Value Stock Options/SARs, ESPP, and Performance Units/Stock-Based Compensation [Abstract]
Weighted Average Fair Value of Grants (price per share) | $ / shares		$ 25.75		$ 22.20		$ 19.21
Expected Volatility (in hundredths)		24.59%		27.12%		36.55%
Risk-Free Interest Rate (in hundredths)		1.89%		0.88%		0.44%
Dividend Yield (in hundredths)		0.64%		0.71%		0.82%
Expected Life (in years)		6 months		6 months		6 months
Stock Options and SARs Rollforward [Abstract]
Approximate Number of Participants		1,934		1,870		1,746
Shares Purchased		180,000		180,000		212,000
Aggregate Purchase Price | $		$ 14,887,000		$ 13,997,000		$ 13,787,000
Restricted Stock and Restricted Stock Units [Member]
Stock Options/SARs and Employee Stock Purchase Plan (ESPP) Disclosures [Line Items]
Unrecognized compensation expense | $		$ 172,000,000
Weighted average period over which unrecognized compensation expense will be recognized				1 year 10 months 24 days
Number of Shares and Units [Roll Forward]
Outstanding at January 1 (in shares)		3,905,000	[3]	3,962,000	[3]	4,908,000
Granted (in shares)		812,000		1,095,000		853,000
Released (in shares)	[4]	(740,000)		(929,000)		(1,465,000)
Forfeited (in shares)		(185,000)		(223,000)		(334,000)
Outstanding at December 31 (in shares)	[3]	3,792,000		3,905,000		3,962,000
Weighted Average Grant Fair Value [Abstract]
Outstanding at January 1 (in dollars per share) | $ / shares		$ 88.57	[3]	$ 79.63	[3]	$ 70.35
Granted (in dollars per share) | $ / shares		117.55		97.34		88.01
Released (in dollars per share) | $ / shares	[4]	78.16		61.51		53.95
Forfeited (in dollars per share) | $ / shares		92.12		85.45		77.29
Outstanding at December 31 (in dollars per share) | $ / shares	[3]	$ 96.64		$ 88.57		$ 79.63
Performance Units and Performance Stock [Abstract]
Compensation expense related to the company's stock-based compensation plans | $		$ 81,000,000		$ 68,000,000		$ 60,000,000
Intrinsic value released during the year | $		84,000,000		91,000,000		124,000,000
Aggregate intrinsic value of stock and unit outstanding | $		331,000,000		$ 421,000,000		$ 401,000,000
Performance Units and Performance Stock [Member]
Stock Options/SARs and Employee Stock Purchase Plan (ESPP) Disclosures [Line Items]
Unrecognized compensation expense | $		$ 10,000,000
Weighted average period over which unrecognized compensation expense will be recognized		1 year 8 months 12 days
Weighted Average Fair Value And Valuation Assumptions Used To Value Stock Options/SARs, ESPP, and Performance Units/Stock-Based Compensation [Abstract]
Weighted Average Fair Value of Grants (price per share) | $ / shares		$ 136.74		$ 113.81		$ 119.10
Expected Volatility (in hundredths)		29.92%		32.19%		32.48%
Risk-Free Interest Rate (in hundredths)		2.85%		1.60%		1.15%
Number of Shares and Units [Roll Forward]
Outstanding at January 1 (in shares)		502,000	[5]	545,000	[5]	405,000
Granted (in shares)		113,000		78,000		132,000
Granted for Performance Multiple (1) (in shares)	[6]	72,000		119,000		142,000
Released (in shares)	[7]	148,000		240,000		134,000
Forfeited (in shares)		0		0		0
Outstanding at December 31 (in shares)	[5]	539,000	[8]	502,000		545,000
Weighted Average Grant Fair Value [Abstract]
Outstanding at January 1 (in dollars per share) | $ / shares		$ 90.96	[5]	$ 80.92	[5]	$ 74.93
Granted (in dollars per share) | $ / shares		125.73		96.29		100.95
Granted for Performance Multiple (1) (in dollars per share) | $ / shares	[6]	101.87		84.43		56.21
Released (in dollars per share) | $ / shares	[7]	84.43		66.69		56.21
Forfeited (in dollars per share) | $ / shares		0.00		0.00		0.00
Outstanding at December 31 (in dollars per share) | $ / shares	[5]	$ 101.53		$ 90.96		$ 80.92
Performance Units and Performance Stock [Abstract]
Minimum Performance Multiple at the Completion Performance Period		0.00%
Maximum Performance Multiple at the Completion Performance Period		200.00%
Minimum Performance Units and Stock Allowed to be Outstanding		144,000
Maximum Performance Units and Stock Allowed to be Outstanding		934,000
Additional Performance Awards Granted		71,805
Compensation expense related to the company's stock-based compensation plans | $		$ 14,000,000		$ 10,000,000		$ 11,000,000
Performance Period		3 years
Intrinsic value released during the year | $		$ 18,000,000		24,000,000		10,000,000
Aggregate intrinsic value of stock and unit outstanding | $		47,000,000		54,000,000		55,000,000
Pension Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Total pension plan costs | $		43,000,000		37,000,000		34,000,000
Company contributions to foreign pension plans | $		1,000,000		1,000,000		1,000,000
Defined Benefit Plan, Benefit Obligation | $		11,000,000		10,000,000
Fair value of foreign pension plan assets | $		9,000,000		8,000,000
Accrued benefit cost | $		(200,000)		(200,000)
Lease And Well [Member]
Performance Units and Performance Stock [Abstract]
Compensation expense related to the company's stock-based compensation plans | $		51,000,000		41,000,000		38,000,000
Gathering And Processing Costs [Member]
Performance Units and Performance Stock [Abstract]
Compensation expense related to the company's stock-based compensation plans | $		1,000,000		1,000,000		1,000,000
Exploration Costs [Member]
Performance Units and Performance Stock [Abstract]
Compensation expense related to the company's stock-based compensation plans | $		25,000,000		23,000,000		21,000,000
General And Administrative [Member]
Performance Units and Performance Stock [Abstract]
Compensation expense related to the company's stock-based compensation plans | $		$ 78,000,000		$ 69,000,000		$ 68,000,000
$ 50.00 to $ 82.99 | Stock Options and Sars [Member]
Summary Information By Grant Price Range For Stock Options And SARs Outstanding And Exercisable At End Of Period [Line Items]
Stock Options and SARs Outstanding		1,528,000
Weighted Average Remaining Life for Outstanding Options and SARs		3 years
Weighted Average Grant Price For Outstanding Options and SARs | $ / shares		$ 65.46
Stock Options and SARs Exercisable		1,183,000
Weighted Average Remaining Life For Exercisable Units		2 years
Weighted Average Grant Price For Exercisable Options and SARs | $ / shares		$ 64.27
83.00 to 95.99 | Stock Options and Sars [Member]
Summary Information By Grant Price Range For Stock Options And SARs Outstanding And Exercisable At End Of Period [Line Items]
Stock Options and SARs Outstanding		2,046,000
Weighted Average Remaining Life for Outstanding Options and SARs		4 years
Weighted Average Grant Price For Outstanding Options and SARs | $ / shares		$ 91.48
Stock Options and SARs Exercisable		1,290,000
Weighted Average Remaining Life For Exercisable Units		3 years
Weighted Average Grant Price For Exercisable Options and SARs | $ / shares		$ 89.50
96.00 to 96.99 | Stock Options and Sars [Member]
Summary Information By Grant Price Range For Stock Options And SARs Outstanding And Exercisable At End Of Period [Line Items]
Stock Options and SARs Outstanding		1,961,000
Weighted Average Remaining Life for Outstanding Options and SARs		6 years
Weighted Average Grant Price For Outstanding Options and SARs | $ / shares		$ 96.29
Stock Options and SARs Exercisable		618,000
Weighted Average Remaining Life For Exercisable Units		5 years
Weighted Average Grant Price For Exercisable Options and SARs | $ / shares		$ 96.29
97.00 to 125.99 | Stock Options and Sars [Member]
Summary Information By Grant Price Range For Stock Options And SARs Outstanding And Exercisable At End Of Period [Line Items]
Stock Options and SARs Outstanding		957,000
Weighted Average Remaining Life for Outstanding Options and SARs		3 years
Weighted Average Grant Price For Outstanding Options and SARs | $ / shares		$ 102.77
Stock Options and SARs Exercisable		872,000
Weighted Average Remaining Life For Exercisable Units		3 years
Weighted Average Grant Price For Exercisable Options and SARs | $ / shares		$ 101.91
126.00 to 129.99 | Stock Options and Sars [Member]
Summary Information By Grant Price Range For Stock Options And SARs Outstanding And Exercisable At End Of Period [Line Items]
Stock Options and SARs Outstanding		1,818,000
Weighted Average Remaining Life for Outstanding Options and SARs		7 years
Weighted Average Grant Price For Outstanding Options and SARs | $ / shares		$ 127.01
Stock Options and SARs Exercisable		6,000
Weighted Average Remaining Life For Exercisable Units		1 year
Weighted Average Grant Price For Exercisable Options and SARs | $ / shares		$ 127.00

[1] The total intrinsic value of stock options/SARs exercised during the years 2018, 2017 and 2016 was $118 million, $95 million and $84 million, respectively. The intrinsic value is based upon the difference between the market price of the Common Stock on the date of exercise and the grant price of the stock options/SARs.

[2] Based upon the difference between the closing market price of the Common Stock on the last trading day of the year and the grant price of in-the-money stock options and SARs.

[3] The total intrinsic value of restricted stock and restricted stock units outstanding at December 31, 2018, 2017 and 2016 was $331 million, $421 million and $401 million, respectively.

[4] The total intrinsic value of restricted stock and restricted stock units released during the years ended December 31, 2018, 2017 and 2016 was $84 million, $91 million and $124 million, respectively. The intrinsic value is based upon the closing price of EOG's common stock on the date restricted stock and restricted stock units are released.

[5] The total intrinsic value of Performance Awards outstanding at December 31, 2018, 2017 and 2016 was $47 million, $54 million and $55 million, respectively.

[6] Upon completion of the Performance Period for the Performance Awards granted in 2014, 2013 and 2012, a performance multiple of 200% was applied to each of the grants resulting in additional grants of Performance Awards in February 2018, 2017 and 2016.

[7] The total intrinsic value of Performance Awards released during the years ended December 31, 2018, 2017 and 2016 was $18 million, $24 million and $10 million, respectively.

[8] Upon the application of the relevant performance multiple at the completion of each of the remaining Performance Periods, a minimum of 144 and a maximum of 934 Performance Awards could be outstanding. The intrinsic value is based upon the closing price of EOG's common stock on the date Performance Awards are released.