2.4.0.8043 - Disclosure - Note 4 - Inventory (Details) - InventorytruefalseIn Thousands, unless otherwise specifiedfalse1false USDfalsefalse$c4_From1Jan2013To30Jun2013http://www.sec.gov/CIK0001023734duration2013-01-01T00:00:002013-06-30T00:00:00usdPerbblDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2009/utrbblutr0usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$c22_From1Jan2012To31Dec2012http://www.sec.gov/CIK0001023734duration2012-01-01T00:00:002012-12-31T00:00:00usdPerbblDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2009/utrbblutr0usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 1bpz_InventoryAbstractbpz_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Inventory [Abstract]2false 2us-gaap_InventoryRawMaterialsAndSuppliesus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefalse1870900018709USD$falsetruefalse2truefalsefalse1834300018343USD$falsetruefalsexbrli:monetaryItemTypemonetaryGross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 6 -Subparagraph a -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(a)(4),(5)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 false2Tubular goods, accessories and spare parts3false 2us-gaap_EnergyRelatedInventoryPetroleumus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefalse13600001360falsefalsefalse2truefalsefalse15080001508falsefalsefalsexbrli:monetaryItemTypemonetaryCarrying amount as of the balance sheet date of petroleum or crude oil.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 6 -Subparagraph a -Article 5 false2Crude oil4false 2us-gaap_InventoryNetus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefalse2006900020069USD$falsetruefalse2truefalsefalse1985100019851USD$falsetruefalsexbrli:monetaryItemTypemonetaryAmount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section 35 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6386567&loc=d3e3927-108312 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6676-107765 false2Inventory5false 2bpz_CrudeOilBarrelsbpz_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefalse1702017020falsefalsefalse2truefalsefalse1787617876falsefalsefalseus-types:perUnitItemTypedecimalCrude oil barrels included in inventory.No definition available.false0Crude oil (barrels) (in Dollars per Barrel (of Oil))6false 2us-gaap_AverageProductionCostsPerBarrelOfOilEquivalentsBOEus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalselabel1truefalsefalse79.9379.93falsefalsefalse2truefalsefalse84.3484.34falsefalsefalseus-types:perUnitItemTypedecimalProduction 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.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Industry Guide -Number 2 -Paragraph 3 -Subparagraph A false0Crude oil (cost per barrel) (in Dollars per Barrel (of Oil))falseNote 4 - Inventory (Details) - Inventory (USD $)ThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://bpzenergy.com/role/InventoryTable26