Fair Value Measurements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Proved Oil and Gas Properties, Other Property, Plant and Equipment and Other Assets [Abstract]
Proved oil and gas properties, other property, plant and equipment and other assets, carrying amount	$ 640,000	$ 778,000
Proved oil and gas properties, other property, plant and equipment and other assets written down during the period - fair value at end of period	372,000	587,000
Pretax impairment charges for proved oil and gas properties and other assets, in which EOG utilized an accepted offer from a third-party purchaser	217,000
Pretax impairment charge for a commodity price-related write-down of other assets	28,000
Pretax impairment charges for proved oil and gas properties, other property, plant and equipment and other assets	268,000	191,000
Pretax impairment charges for obsolete inventory		61,000
Pretax impairment charges for firm commitment contracts		138,000
Debt Disclosure [Abstract]
Aggregate Principal Amount of Current and Long-Term Debt	6,390,000	6,990,000
Debt Instrument, Fair Value Disclosure	6,602,000	7,190,000
Other Liabilities [Member]
Financial Liabilities:
Liabilities, Fair Value Disclosure	7,000
Other Assets [Member]
Financial Assets:
Assets, Fair Value Disclosure	1,000
Assets From Price Risk Management Activities [Member]
Financial Assets:
Assets, Fair Value Disclosure	8,000
Liabilities From Price Risk Management Activities [Member]
Financial Liabilities:
Liabilities, Fair Value Disclosure	50,000	62,000
Commodity Contract [Member] | Crude Oil [Member] | Price Swap [Member]
Financial Liabilities:
Liabilities, Fair Value Disclosure	38,000	36,000
Commodity Contract [Member] | Crude Oil [Member] | Price Swap [Member] | Fair Value, Inputs, Level 1 [Member]
Financial Liabilities:
Liabilities, Fair Value Disclosure	0	0
Commodity Contract [Member] | Crude Oil [Member] | Price Swap [Member] | Fair Value, Inputs, Level 2 [Member]
Financial Liabilities:
Liabilities, Fair Value Disclosure	38,000	36,000
Commodity Contract [Member] | Crude Oil [Member] | Price Swap [Member] | Fair Value, Inputs, Level 3 [Member]
Financial Liabilities:
Liabilities, Fair Value Disclosure	0	0
Commodity Contract [Member] | Crude Oil [Member] | Basis Swaps [Member]
Financial Liabilities:
Liabilities, Fair Value Disclosure	19,000
Commodity Contract [Member] | Crude Oil [Member] | Basis Swaps [Member] | Fair Value, Inputs, Level 1 [Member]
Financial Liabilities:
Liabilities, Fair Value Disclosure	0
Commodity Contract [Member] | Crude Oil [Member] | Basis Swaps [Member] | Fair Value, Inputs, Level 2 [Member]
Financial Liabilities:
Liabilities, Fair Value Disclosure	19,000
Commodity Contract [Member] | Crude Oil [Member] | Basis Swaps [Member] | Fair Value, Inputs, Level 3 [Member]
Financial Liabilities:
Liabilities, Fair Value Disclosure	0
Commodity Contract [Member] | Natural Gas [Member] | Price Swap [Member]
Financial Assets:
Assets, Fair Value Disclosure	2,000
Financial Liabilities:
Liabilities, Fair Value Disclosure		4,000
Commodity Contract [Member] | Natural Gas [Member] | Price Swap [Member] | Fair Value, Inputs, Level 1 [Member]
Financial Assets:
Assets, Fair Value Disclosure	0
Financial Liabilities:
Liabilities, Fair Value Disclosure		0
Commodity Contract [Member] | Natural Gas [Member] | Price Swap [Member] | Fair Value, Inputs, Level 2 [Member]
Financial Assets:
Assets, Fair Value Disclosure	2,000
Financial Liabilities:
Liabilities, Fair Value Disclosure		4,000
Commodity Contract [Member] | Natural Gas [Member] | Price Swap [Member] | Fair Value, Inputs, Level 3 [Member]
Financial Assets:
Assets, Fair Value Disclosure	0
Financial Liabilities:
Liabilities, Fair Value Disclosure		0
Commodity Contract [Member] | Natural Gas [Member] | Options/Collars [Member]
Financial Assets:
Assets, Fair Value Disclosure	6,000	1,000
Financial Liabilities:
Liabilities, Fair Value Disclosure		22,000
Commodity Contract [Member] | Natural Gas [Member] | Options/Collars [Member] | Fair Value, Inputs, Level 1 [Member]
Financial Assets:
Assets, Fair Value Disclosure	0	0
Financial Liabilities:
Liabilities, Fair Value Disclosure		0
Commodity Contract [Member] | Natural Gas [Member] | Options/Collars [Member] | Fair Value, Inputs, Level 2 [Member]
Financial Assets:
Assets, Fair Value Disclosure	6,000	1,000
Financial Liabilities:
Liabilities, Fair Value Disclosure		22,000
Commodity Contract [Member] | Natural Gas [Member] | Options/Collars [Member] | Fair Value, Inputs, Level 3 [Member]
Financial Assets:
Assets, Fair Value Disclosure	$ 0	0
Financial Liabilities:
Liabilities, Fair Value Disclosure		$ 0