SUMMARY OF OIL RESERVES AND SUMMARY OF NATURAL GAS RESERVES - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2011 MetricTon
Reserve Quantities [Line Items]
Percentage of bitumen from total bulk tar sand mined	10.00%
Percentage of bitumen removed by extraction process that is contained within the tar sand	90.00%
Metric tons of oil sand used to produce one barrel of synthetic crude oil	2
Minimum
Reserve Quantities [Line Items]
Catalytic cracking process efficiency level	85.00%
Maximum
Reserve Quantities [Line Items]
Catalytic cracking process efficiency level	90.00%
Canada | Synthetic Oil
Reserve Quantities [Line Items]
Interest in synthetic oil operations at Syncrude in Western Canada, percentage	5.00%
Process of mining tar sands and converting the raw bitumen into a pipeline-quality crude	The proved reserves associated with this project are estimated through a combination of core-hole drilling and realized process efficiencies. The high-density core-hole drilling, at a spacing of less than 500 meters (proved area), provides engineering and geologic data needed to estimate the volumes of tar sand in place and its associated bitumen content. The bitumen generally constitutes approximately 10% of the total bulk tar sand that is mined. The bitumen extraction process is fairly efficient and removes about 90% of the bitumen that is contained within the tar sand. The final step of the process converts the 8.4° API bitumen into 30°-34° API crude oil. A catalytic cracking process is used to crack the long hydrocarbon chains into shorter ones yielding a final crude oil that can be shipped via pipelines. The cracking process has an efficiency ranging from 85% - 90%. Overall, it takes approximately two metric tons of oil sand to produce one barrel of synthetic crude oil. All synthetic oil volumes reported as reserves in this filing are the final synthetic crude oil product.
Malaysia | Oil Reserves
Reserve Quantities [Line Items]
Oil and natural gas reserves associated with the production sharing contracts	104,400,000
Malaysia | Natural Gas Reserves
Reserve Quantities [Line Items]
Oil and natural gas reserves associated with the production sharing contracts	347,800,000,000
Malaysia | Natural Gas Reserves | Kikeh Field
Reserve Quantities [Line Items]
Oil and natural gas reserves associated with the production sharing contracts	94,000,000,000
Natural gas proved reserves expected to receive sale proceeds, per thousand cubic foot	0.24
Republic of the Congo | Oil Reserves
Reserve Quantities [Line Items]
Oil and natural gas reserves associated with the production sharing contracts	2,300,000