Fair Value Measurements (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Financial Liabilities:
Proved Oil and Gas Properties Carrying Amount	$ 94
Proved Oil and Gas Properties Written Down During the Period - Fair value at End of Period	20
Pretax Impairment Charges for Proved Oil and Gas Properties, in which EOG utilized an accepted offer from a third-party buyer	56
Pretax Impairment Charges for Proved Oil and Gas Properties	74
Aggregate Principal Amount of Current and Long-Term Debt	5,890	5,890
Fair Value of Debt	6,254	6,222
Fair Value, Inputs, Level 1 [Member]
Financial Assets:
Financial Assets: Natural Gas Options/Swaptions	0	0
Financial Liabilities:
Financial Liabilities: Crude Oil Swaps	0	0
Financial Liabilities: Crude Oil Options/Swaptions	0	0
Financial Liabilities: Natural Gas Options/Swaptions	0
Financial Liabilities: Foreign Currency Rate Swap		0
Financial Liabilities: Interest Rate Swap		0
Fair Value, Inputs, Level 2 [Member]
Financial Assets:
Financial Assets: Natural Gas Options/Swaptions	12	8
Financial Liabilities:
Financial Liabilities: Crude Oil Swaps	23	17
Financial Liabilities: Crude Oil Options/Swaptions	173	110
Financial Liabilities: Natural Gas Options/Swaptions	31
Financial Liabilities: Foreign Currency Rate Swap		40
Financial Liabilities: Interest Rate Swap		1
Fair Value, Inputs, Level 3 [Member]
Financial Assets:
Financial Assets: Natural Gas Options/Swaptions	0	0
Financial Liabilities:
Financial Liabilities: Crude Oil Swaps	0	0
Financial Liabilities: Crude Oil Options/Swaptions	0	0
Financial Liabilities: Natural Gas Options/Swaptions	0
Financial Liabilities: Foreign Currency Rate Swap		0
Financial Liabilities: Interest Rate Swap		$ 0