Fair Value Measurements (Details) - USD ($)		9 Months Ended
		Sep. 30, 2016		Dec. 31, 2015
Financial Assets:
Financial Assets: Crude Oil Collars		$ 1,000,000
Financial Assets: Natural Gas Price Swaps/Options		4,000,000		$ 0
Proved Oil and Gas Properties, Other Property, Plant and Equipment and Other Assets [Abstract]
Pretax Impairment Charges for Proved Oil and Gas Properties and Other Assets, in which EOG utilized an accepted offer from a third-party purchaser		103,000,000
Pretax Impairment Charges for Proved Oil and Gas Properties, Other Property, Plant and Equipment and Other Assets		107,000,000
Proved Oil and Gas Properties, Other Property, Plant and Equipment and Other Assets Written Down During the Period - Fair value at End of Period		518,000,000
Proved Oil and Gas Properties, Other Property, Plant and Equipment and Other Assets Carrying Amount		625,000,000
Debt Disclosure [Abstract]
Estimated Fair Value of Debt		7,395,000,000		6,524,000,000
Aggregate Principal Amount of Current and Long-Term Debt		6,990,000,000		6,390,000,000
Fair Value, Inputs, Level 1 [Member]
Financial Assets:
Financial Assets: Crude Oil Collars		0
Financial Assets: Natural Gas Price Swaps/Options		0		0
Fair Value, Inputs, Level 2 [Member]
Financial Assets:
Financial Assets: Crude Oil Collars	[1]	1,000,000
Financial Assets: Natural Gas Price Swaps/Options		4,000,000	[1]	0
Fair Value, Inputs, Level 3 [Member]
Financial Assets:
Financial Assets: Crude Oil Collars		0
Financial Assets: Natural Gas Price Swaps/Options		$ 0		$ 0

[1] At September 30, 2016, $2.2 million is included in "Current Assets - Assets From Price Risk Management Activities" and $2.5 million is included in "Other Assets" on the Consolidated Balance Sheets.