Amount of time required to keep a debt service account per agreement

No definition available.

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Namespace Prefix:	bpz_
Data Type:	xbrli:durationItemType
Balance Type:	na
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- Details

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- Definition

The amount of ownership percentage sold in an oil and gas exploration block.

+ References

No definition available.

+ Details

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Namespace Prefix:	bpz_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash inflow associated with funds that are not available for withdrawal or use (such as funds held in escrow) and are associated with underlying transactions that are classified as investing activities.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 1

-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 210.5-02.1)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Cash and equivalents whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements.

+ References

+ Details

Name:	us-gaap_RestrictedCashAndCashEquivalentsNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=bpz_FortyMillionDollarSecuredDebtFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=bpz_SeventyFiveMillionDollarSecuredDebtFacilityMember
Namespace Prefix:
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- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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- Details

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Note 10 - Restricted Cash and Performance Bonds (Details) (USD $)	1 Months Ended			12 Months Ended		0 Months Ended		1 Months Ended
	Apr. 27, 2012	Jul. 31, 2011	Jan. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 14, 2012	Dec. 14, 2012	Sep. 30, 2013	Jul. 31, 2014	May 31, 2012	Dec. 31, 2014	May 31, 2013
Note 10 - Restricted Cash and Performance Bonds (Details) [Line Items]
Debt Instrument, Face Amount			$ 40,000,000us-gaap_DebtInstrumentFaceAmount
Restricted Cash and Cash Equivalents				5,359,000							2,209,000
Debt Service Reserve Period		15 months	18 months
Ownership Percentage Sold, Oil and Gas Exploration Block	49.00%
Restricted Cash and Cash Equivalents, Current				1,250,000							0
Restricted Cash and Cash Equivalents, Noncurrent				4,109,000							2,209,000
Repayments of Debt				99,107,000us-gaap_RepaymentsOfDebt	54,919,000us-gaap_RepaymentsOfDebt
Block Z-1 [Member]
Note 10 - Restricted Cash and Performance Bonds (Details) [Line Items]
Ownership Percentage Sold, Oil and Gas Exploration Block	49.00%					49.00%	49.00%
Debt Reserve Account [Member] \| $75 Million Secured Debt Facility [Member]
Note 10 - Restricted Cash and Performance Bonds (Details) [Line Items]
Restricted Cash and Cash Equivalents		2,500,000
Debt Reserve Account [Member] \| $40 Million Secured Debt Facility [Member]
Note 10 - Restricted Cash and Performance Bonds (Details) [Line Items]
Restricted Cash and Cash Equivalents			2,000,000
Performance-based Arranger Fee [Member] \| $75 Million Secured Debt Facility [Member]
Note 10 - Restricted Cash and Performance Bonds (Details) [Line Items]
Restricted Cash and Cash Equivalents, Current				1,000,000
Debt Reserve Account [Member] \| $40 Million Secured Debt Facility [Member]
Note 10 - Restricted Cash and Performance Bonds (Details) [Line Items]
Repayments of Debt								3,800,000
$75 Million Secured Debt Facility [Member]
Note 10 - Restricted Cash and Performance Bonds (Details) [Line Items]
Debt Instrument, Face Amount		75,000,000										75,000,000
Restricted Cash and Cash Equivalents, Current				0
Restricted Cash and Cash Equivalents, Noncurrent				0
Repayments of Debt										40,000,000
Decrease in Restricted Cash									1,000,000
$40 Million Secured Debt Facility [Member]
Note 10 - Restricted Cash and Performance Bonds (Details) [Line Items]
Debt Instrument, Face Amount			40,000,000					40,000,000				25,500,000
Restricted Cash and Cash Equivalents, Current				1,000,000							0
Restricted Cash and Cash Equivalents, Noncurrent				0							0
Decrease in Restricted Cash									$ 1,000,000