Employee Benefit Plans (Details)		12 Months Ended
		Dec. 31, 2017 USD ($) $ / shares shares		Dec. 31, 2016 USD ($) $ / shares shares		Dec. 31, 2015 USD ($) $ / shares shares
Stock Options/SARs and Employee Stock Purchase Plan (ESPP) Disclosures [Line Items]
Common Shares Available for Grant		17,300,000
Federal income tax (expense) / benefit recognized from stock-based compensation | $		$ 32,000,000
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation | $				$ 29,357,000		$ 26,058,000
Performance Units and Performance Stock [Abstract]
Compensation expense related to the company's stock-based compensation plans | $		133,849,000		128,090,000		130,577,000
Stock Options and Sars [Member]
Stock Options/SARs and Employee Stock Purchase Plan (ESPP) Disclosures [Line Items]
Stock-based compensation expense related to stock options, SAR and ESPP grants | $		$ 56,000,000		$ 57,000,000		$ 56,000,000
Maximum term of stock options and SARs granted		7 years
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		$ 23.95		$ 25.78		$ 21.88
Expected Volatility (in hundredths)		28.28%		31.54%		38.03%
Risk-Free Interest Rate (in hundredths)		1.52%		0.78%		0.83%
Dividend Yield (in hundredths)		0.75%		0.76%		0.85%
Expected Life (in years)		5 years 1 month 6 days		5 years 4 months 24 days		5 years 3 months 18 days
Stock Options and SARs Rollforward [Abstract]
Outstanding at January 1 (in shares)		9,850,000		10,744,000		10,493,000
Granted (in shares)		2,274,000		1,855,000		2,037,000
Exercised (1) (in shares)	[1]	(2,574,000)		(2,376,000)		(1,518,000)
Forfeited (in shares)		(447,000)		(373,000)		(268,000)
Outstanding at December 31 (in shares)		9,103,000		9,850,000		10,744,000
Stock Options/SARs Exercisable at December 31 (in shares)		4,510,000		5,613,000		5,993,000
Stock Options/SARs Exercisable at December 31 (in dollars per share) | $ / shares		$ 75.76		$ 66.48		$ 57.96
Intrinsic value of stock options/SARs exercised during the period | $		$ 95,000,000		$ 84,000,000		$ 60,000,000
Stock Options/SARs Vested or Expected to Vest (in shares)		8,700,000
Weighted average grant price for stock options/SARs vested or expected to vest (per share) | $ / shares		$ 83.56
Intrinsic value of stock options/SARs vested or expected to vest | $		$ 213,000,000
Weighted Average Remaining Contractual Life for Stock Options/SARs Vested or Expected to Vest		4 years 3 months 18 days
Weighted Average Grant Price Stock Option and SARs [Rollfoward]
Outstanding at January 1 (in dollars per share) | $ / shares		$ 75.53		$ 67.98		$ 64.96
Exercised (in dollars per share) | $ / shares	[1]	61.12		54.56		47.64
Granted (in dollars per share) | $ / shares		96.27		94.82		69.99
Forfeited (in dollars per share) | $ / shares		93.84		87.38		80.31
Outstanding at December 31 (in dollars per share) | $ / shares		$ 83.89		75.53		67.98
Performance Units and Performance Stock [Abstract]
Unrecognized compensation expense | $		$ 98,000,000
Weighted average period over which unrecognized compensation expense will be recognized		2 years 4 months 24 days
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		9,103,000
Weighted Average Remaining Life for Outstanding Options and SARs		4 years
Weighted Average Grant Price For Outstanding Options and SARs | $ / shares		$ 83.89
Aggregate Intrinsic Value For Outstanding Options and SARs | $	[2]	$ 218,696
Stock Options and SARs Exercisable		4,510,000
Weighted Average Remaining Life For Exercisable Units		3 years
Weighted Average Grant Price For Exercisable Options and SARs | $ / shares		$ 75.76
Aggregate Intrinsic Value For Exercisable Units | $	[2]	$ 145,024
ESPP [Member]
Stock Options/SARs and Employee Stock Purchase Plan (ESPP) Disclosures [Line Items]
Common Shares Available for Grant		176,000
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		$ 22.20		$ 19.21		$ 21.21
Expected Volatility (in hundredths)		27.12%		36.55%		32.08%
Risk-Free Interest Rate (in hundredths)		0.88%		0.44%		0.12%
Dividend Yield (in hundredths)		0.71%		0.82%		0.73%
Expected Life (in years)		6 months		6 months		6 months
Stock Options and SARs Rollforward [Abstract]
Approximate Number of Participants		1,870		1,746		1,963
Shares Purchased		180,000		212,000		225,000
Aggregate Purchase Price | $		$ 13,997,000		$ 13,787,000		$ 15,045,000
Restricted Stock and Restricted Stock Units [Member]
Number of Shares and Units [Roll Forward]
Outstanding at January 1 (in shares)		3,962,000	[3]	4,908,000	[3]	5,394,000
Granted (in shares)		1,095,000		853,000		1,044,000
Released (in shares)	[4]	(929,000)		(1,465,000)		(1,331,000)
Forfeited (in shares)		(223,000)		(334,000)		(199,000)
Outstanding at December 31 (in shares)	[3]	3,905,000		3,962,000		4,908,000
Weighted Average Grant Fair Value [Abstract]
Outstanding at January 1 (in dollars per share) | $ / shares		$ 79.63	[3]	$ 70.35	[3]	$ 64.39
Granted (in dollars per share) | $ / shares		97.34		88.01		77.94
Released (in dollars per share) | $ / shares	[4]	61.51		53.95		51.52
Forfeited (in dollars per share) | $ / shares		85.45		77.29		74.56
Outstanding at December 31 (in dollars per share) | $ / shares	[3]	$ 88.57		$ 79.63		$ 70.35
Performance Units and Performance Stock [Abstract]
Unrecognized compensation expense | $		$ 173,000,000
Weighted average period over which unrecognized compensation expense will be recognized		2 years 4 months 24 days
Share Based Compensation Arrangement By Restricted Stock And Restricted Stock Units Compensation Cost | $		$ 68,000,000		$ 60,000,000		$ 69,000,000
Intrinsic value released during the year | $		91,000,000		124,000,000		109,000,000
Aggregate intrinsic value of stock and unit outstanding | $		$ 421,000,000		$ 401,000,000		$ 347,000,000
Performance Units and Performance Stock [Member]
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		$ 113.81		$ 119.10		$ 80.64
Expected Volatility (in hundredths)		32.19%		32.48%		29.35%
Risk-Free Interest Rate (in hundredths)		1.60%		1.15%		1.07%
Number of Shares and Units [Roll Forward]
Outstanding at January 1 (in shares)		545,290	[5]	405,000	[5]	333,000
Granted (in shares)		78,527		132,000		72,000
Granted for Performance Multiple (1) (in shares)		118,834		143,000	[6]	0	[6]
Released (in shares)		240,320		134,000	[7]	0	[7]
Forfeited (in shares)		0		0		0
Outstanding at December 31 (in shares)		502,331		545,290	[5]	405,000	[5]
Weighted Average Grant Fair Value [Abstract]
Outstanding at January 1 (in dollars per share) | $ / shares		$ 80.92	[5]	$ 74.93	[5]	$ 76.11
Granted (in dollars per share) | $ / shares		96.29		100.95		69.43
Granted for Performance Multiple (1) (in dollars per share) | $ / shares	[6]	84.43		56.21		0.00
Released (in dollars per share) | $ / shares	[7]	66.69		56.21		0.00
Forfeited (in dollars per share) | $ / shares		0.00		0.00		0.00
Outstanding at December 31 (in dollars per share) | $ / shares	[5]	$ 90.96		$ 80.92		$ 74.93
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%
Term of Zero-Coupon Risk-Free Interest Rate Derived from the Treasury Constant Maturities Yield Curve		3 years 3 months 7 days
Minimum Performance Units and Stock Allowed to be Outstanding		148,444
Maximum Performance Units and Stock Allowed to be Outstanding		856,218
Additional Performance Awards Granted		71,805
Compensation expense related to the company's stock-based compensation plans | $		$ 10,000,000		$ 11,000,000		$ 5,000,000
Unrecognized compensation expense | $		$ 8,300,000
Weighted average period over which unrecognized compensation expense will be recognized		2 years
Performance Period		3 years
Intrinsic value released during the year | $		$ 24,000,000		10,000,000		0
Aggregate intrinsic value of stock and unit outstanding | $		54,000,000		55,000,000		29,000,000
Lease And Well [Member]
Performance Units and Performance Stock [Abstract]
Compensation expense related to the company's stock-based compensation plans | $		41,000,000		38,000,000		44,000,000
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 | $		23,000,000		21,000,000		26,000,000
General And Administrative [Member]
Performance Units and Performance Stock [Abstract]
Compensation expense related to the company's stock-based compensation plans | $		$ 69,000,000		68,000,000		60,000,000
$ 34.00 to $ 59.99 | 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		1,472,000
Weighted Average Remaining Life for Outstanding Options and SARs		1 year
Weighted Average Grant Price For Outstanding Options and SARs | $ / shares		$ 49.63
Stock Options and SARs Exercisable		1,472,000
Weighted Average Remaining Life For Exercisable Units		1 year
Weighted Average Grant Price For Exercisable Options and SARs | $ / shares		$ 49.63
60.00 to 84.99 | 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		2,392,000
Weighted Average Remaining Life for Outstanding Options and SARs		4 years
Weighted Average Grant Price For Outstanding Options and SARs | $ / shares		$ 75.67
Stock Options and SARs Exercisable		1,623,000
Weighted Average Remaining Life For Exercisable Units		3 years
Weighted Average Grant Price For Exercisable Options and SARs | $ / shares		$ 78.51
85.00 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		1,684,000
Weighted Average Remaining Life for Outstanding Options and SARs		6 years
Weighted Average Grant Price For Outstanding Options and SARs | $ / shares		$ 94.82
Stock Options and SARs Exercisable		421,000
Weighted Average Remaining Life For Exercisable Units		5 years
Weighted Average Grant Price For Exercisable Options and SARs | $ / shares		$ 94.73
96.00 to 99.99 | 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		2,239,000
Weighted Average Remaining Life for Outstanding Options and SARs		7 years
Weighted Average Grant Price For Outstanding Options and SARs | $ / shares		$ 96.32
Stock Options and SARs Exercisable		21,000
Weighted Average Remaining Life For Exercisable Units		3 years
Weighted Average Grant Price For Exercisable Options and SARs | $ / shares		$ 98.06
100.00 to 116.99 | 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		1,316,000
Weighted Average Remaining Life for Outstanding Options and SARs		4 years
Weighted Average Grant Price For Outstanding Options and SARs | $ / shares		$ 102.03
Stock Options and SARs Exercisable		973,000
Weighted Average Remaining Life For Exercisable Units		3 years
Weighted Average Grant Price For Exercisable Options and SARs | $ / shares		$ 102.03
Pension Plans [Member]
Defined Benefit and Defined Contribution Plan Disclosure [Line Items]
Total pension plan costs | $		$ 37,000,000		34,000,000		36,000,000
Company contributions to foreign pension plans | $		1,000,000		1,000,000		$ 1,000,000
Benefit obligation | $		10,000,000		8,000,000
Fair value of foreign pension plan assets | $		8,000,000		7,000,000
Accrued benefit cost | $		$ (200,000)		$ (300,000)

[1] The total intrinsic value of stock options/SARs exercised during the years 2017, 2016 and 2015 was $95 million, $84 million and $60 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, 2017, 2016 and 2015 was approximately $421 million, $401 million and $347 million, respectively.

[4] The total intrinsic value of restricted stock and restricted stock units released during the years ended December 31, 2017, 2016 and 2015 was $91 million, $124 million and $109 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, 2017, 2016 and 2015 was approximately $54 million, $55 million and $29 million, respectively.

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

[7] The total intrinsic value of Performance Awards released during the years ended December 31, 2017, 2016 and 2015 was approximately $24 million, $10 million and $0, respectively.