Oil and Gas Exploration and Production Industries Disclosures, Discounted Future Net Cash Flows (Details) $ in Thousands		12 Months Ended
		Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2017 USD ($)		Dec. 31, 2016 USD ($)		Dec. 31, 2015 USD ($)
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Future cash inflows					$ 85,221,064	[1]	$ 58,840,424	[2]	$ 68,720,648	[3]
Future production costs					(32,569,408)		(28,018,883)		(32,060,855)
Future development costs					(13,538,795)		(12,741,932)		(15,785,811)
Future income taxes					(6,160,541)		(3,211,320)		(4,616,201)
Future net cash flows					32,952,320		14,868,289		16,257,781
Discount to present value at 10% annual rate					(14,624,660)		(6,056,132)		(6,636,385)
Standardized measure of discounted future net cash flows relating to proved oil and gas reserves		$ 8,812,157	$ 9,621,396	$ 27,923,418	18,327,660		8,812,157		9,621,396
Annual Rate of Discount to Present Value		10.00%	10.00%	10.00%
Increase (Decrease) in Standardized Measure of Discounted Future Net Cash Flow Relating to Proved Oil and Gas Reserves [Roll Forward]
Balance at Beginning of Period		$ 8,812,157	$ 9,621,396	$ 27,923,418
Sales and transfers of oil and gas produced, net of production costs		(5,605,330)	(3,478,625)	(4,020,717)
Net changes in prices and production costs		7,121,545	(3,679,602)	(30,669,350)
Extensions, discoveries, additions and improved recovery, net of related costs		3,958,248	907,267	1,095,898
Development costs incurred		1,440,300	1,230,000	2,137,700
Revisions of estimated development cost		(124,877)	2,121,708	4,079,381
Revisions of previous quantity estimates		2,438,271	1,053,020	(4,051,874)
Accretion of discount		886,707	1,054,435	3,857,479
Net change in income taxes		(2,043,663)	868,038	9,728,423
Purchases of reserves in place		30,362	377,872	123,542
Sales of reserves in place		(76,527)	(375,793)	(37,088)
Changes in timing and other		1,490,467	(887,559)	(545,416)
Balance at End of Period		18,327,660	8,812,157	9,621,396
United States
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Future cash inflows					83,652,363	[1]	57,913,314	[2]	67,242,928	[3]
Future production costs					(32,018,812)		(27,625,833)		(31,707,743)
Future development costs					(13,395,873)		(12,602,699)		(15,579,923)
Future income taxes					(5,948,453)		(3,151,319)		(4,400,542)
Future net cash flows					32,289,225		14,533,463		15,554,720
Discount to present value at 10% annual rate					(14,532,290)		(6,039,736)		(6,589,253)
Standardized measure of discounted future net cash flows relating to proved oil and gas reserves		8,493,727	8,965,467	26,704,041	$ 17,756,935		$ 8,493,727		$ 8,965,467
Increase (Decrease) in Standardized Measure of Discounted Future Net Cash Flow Relating to Proved Oil and Gas Reserves [Roll Forward]
Balance at Beginning of Period		8,493,727	8,965,467	26,704,041
Sales and transfers of oil and gas produced, net of production costs		(5,387,031)	(3,260,372)	(3,685,600)
Net changes in prices and production costs		6,606,908	(3,352,802)	(29,993,699)
Extensions, discoveries, additions and improved recovery, net of related costs		3,644,041	865,066	1,028,410
Development costs incurred		1,435,600	1,207,000	2,135,800
Revisions of estimated development cost		(114,464)	2,092,769	4,087,093
Revisions of previous quantity estimates		2,460,498	1,013,753	(4,084,572)
Accretion of discount		849,373	970,388	3,699,330
Net change in income taxes		(1,918,989)	738,416	9,550,847
Purchases of reserves in place		30,362	377,872	123,542
Sales of reserves in place		(76,527)	(375,793)	(23,424)
Changes in timing and other		1,733,437	(748,037)	(576,301)
Balance at End of Period		17,756,935	8,493,727	8,965,467
United States | Crude Oil [Member]
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Per unit price used to calculate future cash inflows					49.21		40.70		49.58
United States | Natural Gas Liquids [Member]
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Per unit price used to calculate future cash inflows					23.51		14.69		15.17
United States | Natural Gas [Member]
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Per unit price used to calculate future cash inflows					1.96		1.40		2.15
Trinidad
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Future cash inflows					$ 904,141	[1]	$ 524,523	[2]	$ 954,779	[3]
Future production costs					(239,213)		(165,757)		(183,607)
Future development costs					(84,379)		(103,631)		(140,541)
Future income taxes					(195,855)		(60,001)		(215,659)
Future net cash flows					384,694		195,134		414,972
Discount to present value at 10% annual rate					(52,267)		(9,384)		(33,848)
Standardized measure of discounted future net cash flows relating to proved oil and gas reserves		185,750	381,124	682,536	$ 332,427		$ 185,750		$ 381,124
Increase (Decrease) in Standardized Measure of Discounted Future Net Cash Flow Relating to Proved Oil and Gas Reserves [Roll Forward]
Balance at Beginning of Period		185,750	381,124	682,536
Sales and transfers of oil and gas produced, net of production costs		(254,948)	(215,414)	(351,606)
Net changes in prices and production costs		436,969	(182,876)	(370,503)
Extensions, discoveries, additions and improved recovery, net of related costs		270,255	42,201	47,613
Development costs incurred		4,700	3,900	500
Revisions of estimated development cost		9,683	22,596	(34,647)
Revisions of previous quantity estimates		(58,373)	36,648	33,285
Accretion of discount		24,066	56,566	104,464
Net change in income taxes		(114,575)	129,622	177,576
Purchases of reserves in place		0	0	0
Sales of reserves in place		0	0	0
Changes in timing and other		(171,100)	(88,617)	91,906
Balance at End of Period		332,427	185,750	381,124
Trinidad | Crude Oil [Member]
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Per unit price used to calculate future cash inflows					41.87		34.79		38.83
Trinidad | Natural Gas [Member]
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Per unit price used to calculate future cash inflows					2.76		1.76		2.88
Other International (1)
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Future cash inflows	[4]				$ 664,560	[1]	$ 402,587	[2]	$ 522,941	[3]
Future production costs	[4]				(311,383)		(227,293)		(169,505)
Future development costs	[4]				(58,543)		(35,602)		(65,347)
Future income taxes	[4]				(16,233)		0		0
Future net cash flows	[4]				278,401		139,692		288,089
Discount to present value at 10% annual rate	[4]				(40,103)		(7,012)		(13,284)
Standardized measure of discounted future net cash flows relating to proved oil and gas reserves	[4]	132,680	274,805	536,841	$ 238,298		$ 132,680		$ 274,805
Increase (Decrease) in Standardized Measure of Discounted Future Net Cash Flow Relating to Proved Oil and Gas Reserves [Roll Forward]
Balance at Beginning of Period	[4]	132,680	274,805	536,841
Sales and transfers of oil and gas produced, net of production costs	[4]	36,649	(2,839)	16,489
Net changes in prices and production costs	[4]	77,668	(143,924)	(305,148)
Extensions, discoveries, additions and improved recovery, net of related costs	[4]	43,952	0	19,875
Development costs incurred	[4]	0	19,100	1,400
Revisions of estimated development cost	[4]	(20,096)	6,343	26,935
Revisions of previous quantity estimates	[4]	36,146	2,619	(587)
Accretion of discount	[4]	13,268	27,481	53,685
Net change in income taxes	[4]	(10,099)	0	0
Purchases of reserves in place	[4]	0	0	0
Sales of reserves in place	[4]	0	0	(13,664)
Changes in timing and other	[4]	(71,870)	(50,905)	(61,021)
Balance at End of Period	[4]	$ 238,298	$ 132,680	$ 274,805
Other International (1) | Crude Oil [Member]
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Per unit price used to calculate future cash inflows					50.06		39.55		47.76
Other International (1) | Natural Gas [Member]
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items]
Per unit price used to calculate future cash inflows					5.16		4.84		5.60

[1] Estimated crude oil prices used to calculate 2017 future cash inflows for the United States, Trinidad and Other International were $49.21, $41.87 and $50.06, respectively. Estimated NGL price used to calculate 2017 future cash inflows for the United States was $23.51. Estimated natural gas prices used to calculate 2017 future cash inflows for the United States, Trinidad and Other International were $1.96, $2.76 and $5.16, respectively.

[2] Estimated crude oil prices used to calculate 2016 future cash inflows for the United States, Trinidad and Other International were $40.70, $34.79 and $39.55, respectively. Estimated NGL price used to calculate 2016 future cash inflows for the United States was $14.69. Estimated natural gas prices used to calculate 2016 future cash inflows for the United States, Trinidad and Other International were $1.40, $1.76 and $4.84, respectively.

[3] Estimated crude oil prices used to calculate 2015 future cash inflows for the United States, Trinidad and Other International were $49.58, $38.83 and $47.76, respectively. Estimated NGL price used to calculate 2015 future cash inflows for the United States was $15.17. Estimated natural gas prices used to calculate 2015 future cash inflows for the United States, Trinidad and Other International were $2.15, $2.88 and $5.60, respectively.

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