| Production costs incurred in lifting the oil and gas to the surface during the reporting period divided by the number of barrels of oil equivalents (BOE) produced. Production (or lifting costs) are costs incurred in lifting the oil and gas to the surface and generally include gathering, treating, primary processing, field storage, property taxes and insurance on proved properties, but do not include depreciation, depletion, accretion, amortization, royalties, income taxes, interest, general and administrative and other expenses. | en-US | http://www.xbrl.org/2003/role/documentation | http://www.xbrl.org/2003/role/link |