Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018		Dec. 31, 2017	Dec. 31, 2016		Jan. 01, 2018
Total Operating Revenues and Other	$ 4,574,536	$ 4,781,624	$ 4,238,077	$ 3,681,162	$ 3,340,439	$ 2,644,844	$ 2,612,472	$ 2,610,565	$ 17,275,399		$ 11,208,320	$ 7,650,632	[1]
Gathering and Processing Costs									436,973	[2],[3]	148,775	122,901
Marketing Costs									5,203,243		3,330,237	2,007,635
Total Operating Expenses									12,806,053		10,281,918	8,875,913
Operating Income	1,123,140	$ 1,506,687	$ 964,931	$ 874,588	$ 475,912	$ 214,836	$ 127,908	$ 107,746	4,469,346		926,402	(1,225,281)
Accounts Receivable From Contracts With Customers	1,460,000								1,460,000					$ 1,343,000
Crude Oil and Condensate
Revenues									9,517,440		6,256,396	4,317,341
Natural Gas Liquids
Revenues									1,127,510		729,561	437,250
Natural Gas
Revenues									1,301,537		921,934	742,152
Gathering, Processing and Marketing
Revenues									5,230,355		$ 3,298,087	$ 1,966,259
Accounting Standards Update 2014-09 [Member]
Total Operating Revenues and Other									17,052,465
Gathering and Processing Costs									233,258
Marketing Costs									5,184,024
Total Operating Expenses									12,583,119
Operating Income									4,469,346
Accounting Standards Update 2014-09 [Member] | Crude Oil and Condensate
Revenues									9,517,440
Accounting Standards Update 2014-09 [Member] | Natural Gas Liquids
Revenues									1,121,237
Accounting Standards Update 2014-09 [Member] | Natural Gas
Revenues									1,104,095
Accounting Standards Update 2014-09 [Member] | Gathering, Processing and Marketing
Revenues									5,211,136
Effect of Change [Member]
Total Operating Revenues and Other									222,934
Gathering and Processing Costs									203,715
Marketing Costs									19,219
Total Operating Expenses									222,934
Operating Income									0
Effect of Change [Member] | Crude Oil and Condensate
Revenues									0
Effect of Change [Member] | Natural Gas Liquids
Revenues									6,273
Effect of Change [Member] | Natural Gas
Revenues									197,442
Effect of Change [Member] | Gathering, Processing and Marketing
Revenues									19,219
Accounting Standards Update 2016-02 [Member]
Finance Lease, Liability, Undiscounted Excess Amount	$ 2,000,000								$ 2,000,000

[1] 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 Operating Revenues and Other in the United States segment.

[2] Effective January 1, 2018, EOG adopted the provisions of Accounting Standards Update (ASU) 2014-09, "Revenue From Contracts With Customers" (ASU 2014-09). In connection with the adoption of ASU 2014-09, EOG presents natural gas processing fees relating to certain processing and marketing agreements within its United States segment as Gathering and Processing Costs instead of as a deduction to Natural Gas Revenues. There was no impact to operating income or net income resulting from changes to the presentation of natural gas processing fees (see Note 1 to Consolidated Financial Statements).

[3] 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, 2018.