2.4.0.8067 - Disclosure - Note 12 - Stockholders' Equity (Details)truefalsefalse1false USDfalsefalse$c155_From1Jul2013To2Jul2013http://www.sec.gov/CIK0001023734duration2013-07-01T00:00:002013-07-02T00:00:00sharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0usdPersharesDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2false falsefalsec0_AsOf30Jun2013http://www.sec.gov/CIK0001023734instant2013-06-30T00:00:000001-01-01T00:00:00sharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli03false falsefalsec1_AsOf31Dec2012http://www.sec.gov/CIK0001023734instant2012-12-31T00:00:000001-01-01T00:00:00sharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli04false truefalsec145_From1Mar2013To31Mar2013_RestrictedStockMember_TwoThousandSevenLongTermIncentiveCompensationPlanMemberhttp://www.sec.gov/CIK0001023734duration2013-03-01T00:00:002013-03-31T00:00:00falsefalseRestricted Stock [Member]us-gaap_AwardTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_RestrictedStockMemberus-gaap_AwardTypeAxisexplicitMemberfalsefalse2007 Long-Term Incentive Compensation Plan [Member]us-gaap_PlanNameAxisxbrldihttp://xbrl.org/2006/xbrldibpz_TwoThousandSevenLongTermIncentiveCompensationPlanMemberus-gaap_PlanNameAxisexplicitMembersharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli05false USDtruefalse$c146_From1Jan2013To30Jun2013_RestrictedStockMember_TwoThousandSevenLongTermIncentiveCompensationPlanMemberhttp://www.sec.gov/CIK0001023734duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRestricted Stock [Member]us-gaap_AwardTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_RestrictedStockMemberus-gaap_AwardTypeAxisexplicitMemberfalsefalse2007 Long-Term Incentive Compensation Plan [Member]us-gaap_PlanNameAxisxbrldihttp://xbrl.org/2006/xbrldibpz_TwoThousandSevenLongTermIncentiveCompensationPlanMemberus-gaap_PlanNameAxisexplicitMemberusdPersharesDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$6false truefalsec152_AsOf30Jun2013_PerEmployeeMember_EmployeeStockPurchasePlanMemberhttp://www.sec.gov/CIK0001023734instant2013-06-30T00:00:000001-01-01T00:00:00falsefalsePer Employee [Member]us-gaap_AwardTypeAxisxbrldihttp://xbrl.org/2006/xbrldibpz_PerEmployeeMemberus-gaap_AwardTypeAxisexplicitMemberfalsefalseEmployee Stock Purchase Plan [Member]us-gaap_PlanNameAxisxbrldihttp://xbrl.org/2006/xbrldibpz_EmployeeStockPurchasePlanMemberus-gaap_PlanNameAxisexplicitMembersharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli07false truefalsec149_From1Mar2013To31Mar2013_TwoThousandSevenLongTermIncentiveCompensationPlanMemberhttp://www.sec.gov/CIK0001023734duration2013-03-01T00:00:002013-03-31T00:00:00falsefalse2007 Long-Term Incentive Compensation Plan [Member]us-gaap_PlanNameAxisxbrldihttp://xbrl.org/2006/xbrldibpz_TwoThousandSevenLongTermIncentiveCompensationPlanMemberus-gaap_PlanNameAxisexplicitMembersharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli08false USDtruefalse$c151_From1Jan2013To30Jun2013_TwoThousandSevenLongTermIncentiveCompensationPlanMemberhttp://www.sec.gov/CIK0001023734duration2013-01-01T00:00:002013-06-30T00:00:00falsefalse2007 Long-Term Incentive Compensation Plan [Member]us-gaap_PlanNameAxisxbrldihttp://xbrl.org/2006/xbrldibpz_TwoThousandSevenLongTermIncentiveCompensationPlanMemberus-gaap_PlanNameAxisexplicitMemberusdPersharesDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0sharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDUSD$9false truefalsec147_From1Mar2013To31Mar2013_TwoThousandSevenDirectorsCompensationIncentivePlanMemberhttp://www.sec.gov/CIK0001023734duration2013-03-01T00:00:002013-03-31T00:00:00falsefalse2007 Directors' Compensation Incentive Plan [Member]us-gaap_PlanNameAxisxbrldihttp://xbrl.org/2006/xbrldibpz_TwoThousandSevenDirectorsCompensationIncentivePlanMemberus-gaap_PlanNameAxisexplicitMembersharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli010false USDtruefalse$c148_From1Jan2013To30Jun2013_TwoThousandSevenDirectorsCompensationIncentivePlanMemberhttp://www.sec.gov/CIK0001023734duration2013-01-01T00:00:002013-06-30T00:00:00falsefalse2007 Directors' Compensation Incentive Plan [Member]us-gaap_PlanNameAxisxbrldihttp://xbrl.org/2006/xbrldibpz_TwoThousandSevenDirectorsCompensationIncentivePlanMemberus-gaap_PlanNameAxisexplicitMemberusdPersharesDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0sharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDUSD$11false truefalsec153_AsOf30Jun2013_EmployeeStockPurchasePlanMemberhttp://www.sec.gov/CIK0001023734instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseEmployee Stock Purchase Plan [Member]us-gaap_PlanNameAxisxbrldihttp://xbrl.org/2006/xbrldibpz_EmployeeStockPurchasePlanMemberus-gaap_PlanNameAxisexplicitMemberpureStandardhttp://www.xbrl.org/2003/instancepurexbrli012false truefalsec154_AsOf30Jun2011_EmployeeStockPurchasePlanMemberhttp://www.sec.gov/CIK0001023734instant2011-06-30T00:00:000001-01-01T00:00:00falsefalseEmployee Stock Purchase Plan [Member]us-gaap_PlanNameAxisxbrldihttp://xbrl.org/2006/xbrldibpz_EmployeeStockPurchasePlanMemberus-gaap_PlanNameAxisexplicitMembersharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli013false truefalsec150_From1Mar2013To31Mar2013_TwoThousandSevenLongTermIncentiveCompensationPlanMemberhttp://www.sec.gov/CIK0001023734duration2013-03-01T00:00:002013-03-31T00:00:00falsefalse2007 Long-Term Incentive Compensation Plan [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldibpz_TwoThousandSevenLongTermIncentiveCompensationPlanMemberus-gaap_RangeAxisexplicitMember1true 3bpz_Note12StockholdersEquityDetailsLineItemsbpz_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Note 12 - Stockholders' Equity (Details) [Line Items]2false 4us-gaap_PreferredStockSharesAuthorizedus-gaap_truenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse2500000025000000falsefalsefalse3truefalsefalse2500000025000000falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalsexbrli:sharesItemTypesharesThe maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.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 210.5-02.28) -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 29 -Article 5 false1Preferred Stock, Shares Authorized3false 4us-gaap_CommonStockSharesAuthorizedus-gaap_truenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse250000000250000000falsefalsefalse3truefalsefalse250000000250000000falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalsexbrli:sharesItemTypesharesThe maximum number of common shares permitted to be issued by an entity's charter and bylaws.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 210.5-02.29) -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 30 -Article 5 false1Common Stock, Shares Authorized4false 4us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorizedus-gaap_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:sharesItemTypesharesThe maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 false1Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized5false 4us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantus-gaap_truenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse19481161948116falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8truefalsefalse800000800000falsefalsefalse9falsefalsefalse00falsefalsefalse10truefalsefalse500000500000falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalsexbrli:sharesItemTypesharesThe difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 false1Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant6false 4us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4truefalsefalse644190644190falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9truefalsefalse238973238973falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalsexbrli:sharesItemTypesharesThe number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 false1Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period7false 4us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValueus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse2.722.72USD$falsetruefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10truefalsefalse2.722.72USD$falsetruefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalsenum:perShareItemTypedecimalThe weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 false3Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share)8false 4us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGrossus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7truefalsefalse802678802678falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalsexbrli:sharesItemTypesharesGross number of share options (or share units) granted during the period.No definition available.false1Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross9false 4us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1us-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse003 yearsfalsefalsefalsexbrli:durationItemTypenaPeriod which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 false0Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period10false 4us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePriceus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8truefalsefalse2.722.72USD$falsetruefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalsenum:perShareItemTypedecimalWeighted average per share amount at which grantees can acquire shares of common stock by exercise of options.No definition available.false3Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in Dollars per share)11false 4us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValueus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8truefalsefalse1.781.78USD$falsetruefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalsenum:perShareItemTypedecimalThe weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 false3Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share)12false 4bpz_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorizedPerEmployeePerOfferingPeriodbpz_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6truefalsefalse25002500falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalsexbrli:sharesItemTypesharesEmployees will be allowed to purchase up to 2,500 shares in any one offering period (not longer than twenty-seven months), within IRS limitations and plan rules.No definition available.false1Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized Per Employee Per Offering Period13false 4bpz_LengthOfOfferingPeriodbpz_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse0027 monthsfalsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalsexbrli:durationItemTypenaLength of offering period.No definition available.false0Length Of Offering Period14false 4bpz_PurchasePricePercentOfFairValuebpz_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsetruefalse00falsefalsefalse2falsetruefalse00falsefalsefalse3falsetruefalse00falsefalsefalse4falsetruefalse00falsefalsefalse5falsetruefalse00falsefalsefalse6falsetruefalse00falsefalsefalse7falsetruefalse00falsefalsefalse8falsetruefalse00falsefalsefalse9falsetruefalse00falsefalsefalse10falsetruefalse00falsefalsefalse11truetruefalse0.850.85falsefalsefalse12falsetruefalse00falsefalsefalse13falsetruefalse00falsefalsefalsenum:percentItemTypepurePurchase price percent of fair value.No definition available.false0Purchase Price Percent Of Fair Value15false 4us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlansus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse72837283falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalsexbrli:sharesItemTypesharesNumber of shares issued during the period as a result of an employee stock purchase plan.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 false1Stock Issued During Period, Shares, Employee Stock Purchase Plans16false 4us-gaap_EmployeeStockOwnershipPlanESOPWeightedAveragePurchasePriceOfSharesPurchasedus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1.521.52USD$falsetruefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse7falsefalsefalse00falsefalsefalse8falsefalsefalse00falsefalsefalse9falsefalsefalse00falsefalsefalse10falsefalsefalse00falsefalsefalse11falsefalsefalse00falsefalsefalse12falsefalsefalse00falsefalsefalse13falsefalsefalse00falsefalsefalsenum:perShareItemTypedecimalWeighted average purchase price of capital shares purchased through an employee stock ownership plan.No definition available.false3Employee Stock Ownership Plan (ESOP), Weighted Average Purchase Price of Shares Purchased (in Dollars per share)falseNote 12 - Stockholders' Equity (Details) (USD $)UnKnownNoRoundingNoRoundingUnKnowntruefalsefalseSheethttp://bpzenergy.com/role/Note12StockholdersEquityDetails1316