No authoritative reference available.

No definition available.

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- Definition

The tax rate of foreign income taxes, stated as a percentage.

+ References

No definition available.

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- Definition

Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences expected to be realized or consumed after one year (or the normal operating cycle, if longer).

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local operating loss carryforwards.

+ References

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign operating loss carryforwards.

+ References

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Glossary Income Tax Expense (or Benefit)

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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-Glossary Unrecognized Tax Benefit

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Note 20 - Income Tax (Details) (USD $)	3 Months Ended		12 Months Ended
Note 20 - Income Tax (Details) (USD $)	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Note 20 - Income Tax (Details) [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards	$ 80,170,000		$ 80,170,000	$ 77,588,000
Efffect of Future Reversal of Peruvian Deferred Tax Assets and Liabilities On Impact of Peruvian Employee Profit Share Plan			0	7,000,000
Income Tax Expense (Benefit)	32,300,000us-gaap_IncomeTaxExpenseBenefit	9,900,000us-gaap_IncomeTaxExpenseBenefit	30,974,000us-gaap_IncomeTaxExpenseBenefit	(5,775,000)us-gaap_IncomeTaxExpenseBenefit	(15,614,000)us-gaap_IncomeTaxExpenseBenefit
Deferred Tax Assets, Operating Loss Carryforwards, Domestic	62,700,000		62,700,000
Deferred Tax Assets, Valuation Allowance	92,308,000		92,308,000	50,601,000
Deferred Tax Assets, Operating Loss Carryforwards, Foreign	17,500,000		17,500,000
Foreign Income Tax Rate			22.00%bpz_ForeignIncomeTaxRate
Deferred Tax Assets, Net, Noncurrent	33,997,000		33,997,000	63,602,000
Unrecognized Tax Benefits	715,000us-gaap_UnrecognizedTaxBenefits		715,000us-gaap_UnrecognizedTaxBenefits	668,000us-gaap_UnrecognizedTaxBenefits	0us-gaap_UnrecognizedTaxBenefits	0us-gaap_UnrecognizedTaxBenefits
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	47,000		47,000	46,000	0
Domestic Tax Authority [Member]
Note 20 - Income Tax (Details) [Line Items]
Deferred Tax Assets, Valuation Allowance	50,100,000		50,100,000
Foreign Tax Authority [Member]
Note 20 - Income Tax (Details) [Line Items]
Deferred Tax Assets, Net, Noncurrent	34,000,000		34,000,000
Peruvian Employee Profit Sharing Plan [Member]
Note 20 - Income Tax (Details) [Line Items]
Income Tax Expense (Benefit)			6,400,000
Various Deferred Tax Assets Items [Member]
Note 20 - Income Tax (Details) [Line Items]
Income Tax Expense (Benefit)			42,200,000
Overhead Allocations and Exploration Activities [Member]
Note 20 - Income Tax (Details) [Line Items]
Income Tax Expense (Benefit)			1,900,000
The 2011 through 2013 Net Operating Losses [Member]
Note 20 - Income Tax (Details) [Line Items]
Income Tax Expense (Benefit)			15,400,000
Certain Overhead Expenses [Member]
Note 20 - Income Tax (Details) [Line Items]
Income Tax Expense (Benefit)			6,700,000
Foreign Subsidiary [Member]
Note 20 - Income Tax (Details) [Line Items]
Deferred Tax Assets, Valuation Allowance	11,800,000		11,800,000
Gross [Member]
Note 20 - Income Tax (Details) [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards	$ 80,200,000		$ 80,200,000