Note 10 - Debt (Details) (USD $)	1 Months Ended	3 Months Ended		6 Months Ended			11 Months Ended	42 Months Ended							3 Months Ended		19 Months Ended		3 Months Ended			42 Months Ended		12 Months Ended	6 Months Ended		3 Months Ended		6 Months Ended	12 Months Ended	2 Months Ended	3 Months Ended	6 Months Ended	42 Months Ended			1 Months Ended	3 Months Ended		6 Months Ended	12 Months Ended		3 Months Ended	6 Months Ended
	May 31, 2012	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2012	Dec. 31, 2013	Jun. 30, 2013	Jul. 31, 2011	Jan. 31, 2011	Mar. 31, 2010	Jun. 30, 2013 Capital and Exploratory Expenditures [Member] Block Z-1 [Member] $75 Million Secured Debt Facility [Member]	Dec. 31, 2012 Capital and Exploratory Expenditures [Member] Block XIX [Member] $75 Million Secured Debt Facility [Member]	Jun. 30, 2013 Estimated [Member] $170.9 Million Convertible Notes [Member]	Jun. 30, 2013 Fees and Prepayment Premium [Member] $75 Million Secured Debt Facility [Member]	Jun. 30, 2013 Remaining Unamortized Debt Issue Costs [Member] $75 Million Secured Debt Facility [Member]	Jan. 31, 2015 Original Amount [Member]	Jan. 31, 2015 New Amount [Member]	Mar. 31, 2010 Direct Offering Expenses [Member] $170.9 Million Convertible Notes [Member]	Mar. 31, 2010 Amortized As Non-Cash Interest Expense [Member] $170.9 Million Convertible Notes [Member]	Mar. 31, 2010 Allocated To Equity Component Of Convertible Debt [Member] $170.9 Million Convertible Notes [Member]	Jun. 30, 2013 Shares [Member] $170.9 Million Convertible Notes [Member]	Jun. 30, 2013 Per Principal Amount [Member] $170.9 Million Convertible Notes [Member]	Dec. 31, 2012 Additional Funding [Member] $75 Million Secured Debt Facility [Member]	Jun. 30, 2013 Additional Funding [Member] $40 Million Secured Debt Facility [Member]	Jun. 30, 2013 Original [Member] $40 Million Secured Debt Facility [Member]	Mar. 31, 2010 Commissions In Connection With Offerring [Member] $170.9 Million Convertible Notes [Member]	Jun. 30, 2012 $75 Million Secured Debt Facility [Member]	Jun. 30, 2013 $75 Million Secured Debt Facility [Member]	Dec. 31, 2012 $40 Million Secured Debt Facility [Member]	Mar. 31, 2011 $170.9 Million Convertible Notes [Member]	Mar. 31, 2010 $170.9 Million Convertible Notes [Member]	Jun. 30, 2013 $170.9 Million Convertible Notes [Member]	Jun. 30, 2013 $170.9 Million Convertible Notes [Member]	Dec. 31, 2012 $170.9 Million Convertible Notes [Member]	Mar. 31, 2010 Equity Component Of $170.9 Million Convertible Debt [Member]	Jul. 31, 2011 $75 Million Secured Debt Facility [Member]	Dec. 31, 2012 $75 Million Secured Debt Facility [Member]	Jun. 30, 2012 $75 Million Secured Debt Facility [Member]	Jun. 30, 2013 $75 Million Secured Debt Facility [Member]	Dec. 31, 2012 $75 Million Secured Debt Facility [Member]	Mar. 31, 2012 $75 Million Secured Debt Facility [Member]	Dec. 31, 2012 $40 Million Secured Debt Facility [Member]	Jun. 30, 2013 $40 Million Secured Debt Facility [Member]	May 31, 2013 $40 Million Secured Debt Facility [Member]	Jan. 31, 2011 $40 Million Secured Debt Facility [Member]	Jun. 30, 2013 $75 Million Secured Debt Facility [Member]	Jun. 30, 2013 Maximum [Member] $75 Million Secured Debt Facility [Member]
Note 10 - Debt (Details) [Line Items]
Convertible Debt, Noncurrent		$ 170,900,000		$ 170,900,000	$ 170,900,000			$ 170,900,000			$ 170,900,000																						$ 170,900,000	$ 170,900,000	$ 170,900,000
Debt Instrument, Interest Rate, Stated Percentage		6.50%		6.50%	6.50%			6.50%																								6.50%	6.50%	6.50%	6.50%
Debt Instrument, Convertible, Conversion Ratio				1,000																		148.3856	1,000								169.0082		169.0082
Debt Instrument, Convertible, Conversion Price (in Dollars per share)																															$ 5.9169	$ 6.74
Debt Instrument, Convertible, Terms of Conversion Feature							As of February3, 2013, the Company may redeem for cash all or a portion of the 2015 Convertible Notes at a redemption price of 100% of the principal amount of the notes to be redeemed plus any accrued and unpaid interest to, but not including, the redemption date, plus a "make-whole" payment if: (1)for at least 20 trading days in any consecutive 30 trading days ending within 5 trading days immediately before the date the Company mails the redemption notice, the "last reported sale price" of its common stock exceeded 175% of the conversion price in effect on that trading day, and (2)there is no continuing default with respect to the notes that has not been cured or waived on or before the redemption date.																											during any fiscal quarter (and only during such fiscal quarter) commencing after March31, 2010, if the last reported sale price of the Company's common stock is greater than or equal to 130% of the conversion price of the 2015 Convertible Notes for at least 20 trading days in the period of 30 consecutive trading days ending on the last trading day of the preceding fiscal quarter; (2)prior to January1, 2015, during the five business-day period after any ten consecutive trading-day period in which the trading price of $1,000 principal amount of the 2015 Convertible Notes for each trading day in the measurement period was less than 97% of the product of the last reported sale price of the Company's common stock and the conversion rate on such trading day; (3)if the 2015 Convertible Notes have been called for redemption; or (4)upon the occurrence of one of a specified number of corporate transactions. Holders may also convert the 2015 Convertible Notes at their option at any time beginning on February1, 2015, and ending at the close of business on the second business day immediately preceding the maturity date.
Percent of Principal Subject to Repurchase																																100.00%
Proceeds from Issuance of Debt				14,500,000																												164,900,000												14,500,000
Payments of Debt Issuance Costs								4,800,000											600,000	4,800,000	1,300,000			1,100,000	1,800,000		5,500,000					6,100,000
Debt Instrument, Interest Rate, Effective Percentage														12.00%																			12.60%	12.60%
Convertible Debt Net Of Discount																																136,300,000
Debt Instrument, Unamortized Discount		13,800,000		13,800,000	17,400,000			13,800,000																								34,600,000	13,800,000	13,800,000	17,400,000
Convertible Debt		157,132,000		157,132,000	153,479,000			157,132,000																									157,100,000	157,100,000
Debt Instrument, Convertible, Carrying Amount of Equity Component																																	33,300,000	33,300,000
Debt Instrument Convertible Carrying Amount Of The Equity Component Initial Discount																																				34,600,000
Debt Instrument Convertible Carrying Amount Of The Equity Component Direct Transaction Costs																																				1,300,000
Debt Instrument, Convertible, Number of Equity Instruments																																	28,900,000
Stock Price Per Share (in Dollars per share)		$ 1.79		$ 1.79				$ 1.79
Debt Instrument, Face Amount (in Dollars)									75,000,000	40,000,000																											75,000,000	75,000,000		75,000,000	75,000,000		40,000,000	40,000,000	25,500,000	40,000,000	25,500,000
Repayments of Debt	40,000,000			46,139,000		44,735,000																															40,000,000							43,829,000
Debt Instrument, Collateral																													the $75.0 million secured debt facility were utilized to pay certain fees and expenses under the $75.0 million secured debt facility, to fund a debt service reserve account under the $75.0 million secured debt facility, to reimburse certain affiliates of BPZ E&P for up to $14.0 million of capital and exploratory expenditures incurred by them in connection with the development of Block Z-1 and up to $6.0 million of capital and exploratory expenditures incurred by them in connection with the development in Block XIX in northwest Peru, and to finance BPZ E&P's capital and exploratory expenditures in connection with the development of Block Z-1. As a result of the prepayment of the remaining principal balance during the second quarter of 2013, the Company incurred $2.4 million of fees and a prepayment premium. The $2.4 million in fees and prepayment premium were recognized as a "Loss on extinguishment of debt" in the Consolidated Statement of Operations. Approximately $1.4 million representing the remaining unamortized debt issue costs loan was expensed as a "Loss on extinguishment of debt" in the Consolidated Statement of Operations when the Company prepaid the remaining principal. For further information on debt issue costs see Note-5, "Prepaid and Other Current Assets and Other Non-Current Assets." As a result of the prepayment and amendment during the second quarter of 2012, the Company incurred $5.8 million of fees and a prepayment premium and $1.1 million of debt issue costs. The $5.8 million in fees and prepayment premium were recognized as a "Loss on extinguishment of debt" in the Consolidated Statement of Operations, of which 25% was paid at the time of the amendment and prepayment and 25% was paid at the time of each of the next three quarterly interest payment dates ending in January 2013. Approximately $1.5 million of the remaining $2.8 million of unamortized debt issue costs associated with the initial loan was expensed as a "Loss on extinguishment of debt" in the Consolidated Statement of Operations when the Company prepaid $40.0 million of principal. For further information on debt issue costs see Note-5, "Prepaid and Other Current Assets and Other Non-Current Assets." The $75.0 million secured debt facility, as amended, provides for an ongoing fee through July 2014 payable by BPZ E&P to the lenders, of the performance based arranger fee (the "Performance Based Arranger Fee") whose amount is determined by the change in the price of Brent crude oil at inception of the loans and the price at each principal repayment date in accordance with the original loan principal repayment dates, subject to a 12% ceiling of the original principal amount borrowed. For further information on the Performance Based Arranger Fee, see Note-11, "Derivative Financial Instruments" and Note -13, " Fair Value Measurements and Disclosures." $40.0 Million Secured Debt Facility In January2011, the Company, through its subsidiaries, completed a credit agreement with Credit Suisse where Credit Suisse provided a $40.0 million secured debt facility to the Company's power generation subsidiary, Empresa Elctrica Nueva Esperanza S.R.L. On April27, 2012, the Company and its subsidiaries, Empresa Elctrica Nueva Esperanza S.R.L. and BPZ E&P, entered into a fourth amendment to the $40.0 million secured debt facility with Credit Suisse. In May 2013, the Company amended and restated the $40.0 million secured debt facility (which had been repaid by scheduled principal repayments to $25.5 million) by increasing the facility size and borrowing an additional $14.5 million. In 2013, the $14.5 million of proceeds from the amended and restated $40.0 million secured debt facility will be utilized to meet the Company's 2013 capital, exploration and development work programs as well as general corporate purposes. In 2011, the proceeds from the $40.0 million secured debt facility were utilized to meet the Company's 2011 capital, exploration and development work programs, and to reduce other debt obligations. In May 2013, as a result of amending and restating the $40.0 million secured debt facility (which had been repaid by scheduled principal repayments to $25.5 million) by increasing the facility size and borrowing an additional $14.5 million, the Company added $1.8 million of debt issue costs. The $1.8 million of new debt issue costs was combined with the remaining $0.6 million of unamortized debt issue costs and will be amortized over the remaining term, ending in January 2015, using the effective interest method. For further information on debt issue costs, see Note-5, "Prepaid and Other Current Assets and Other Non-Current Assets." The $40.0 million secured debt facility, as amended, provides for ongoing fees payable to Credit Suisse including a Performance Based Arranger Fee whose amount is determined by the change in the price of Brent crude oil at inception of the loan and the price at each principal repayment date in accordance with the original loan principal repayment dates, subject to a 18% ceiling of the original principal amount borrowed. For further information on the Performance Based Arranger Fee, see Note-11, "Derivative Financial Instruments" and Note -13, " Fair Value Measurements and Disclosures." The $40.0 million secured debt facility is secured by three LM6000 gas-fired packaged power units (approximately $53.0 million) that were purchased by the Company from GE through its power generation subsidiary, Empresa Elctrica Nueva Esperanza S.R.L. and the associated debt service reserve account. The Company and its subsidiary, BPZ E&P, also agreed to unconditionally guarantee the $40.0 million secured debt facility on an unsecured basis.
Debt Instrument Reimburse Certain Affiliates												14,000,000	6,000,000
Gains (Losses) on Extinguishment of Debt		(3,786,000)	(7,318,000)	(3,786,000)		(7,318,000)									2,400,000	(1,400,000)												(1,500,000)											5,800,000		(1,500,000)
Debt Issuance Cost			1,100,000
Fees Prepayment Penalty And Debt Issuance Cost Payment Percentage			25.00%		25.00%
Unamortized Debt Issuance Expense																										600,000			2,800,000													2,800,000
Arranger Fee					18.00%																																			12.00%				18.00%				12.00%
Collateral Already Posted, Aggregate Fair Value																																												53,000,000
Debt Instrument, Periodic Payment, Principal																	$ 4,000,000	$ 9,000,000
Debt Instrument, Interest Rate Terms				LIBOR rate plus 8%																										three month LIBOR rate plus 8%								three month LIBOR plus 9%		three month LIBOR plus 9%			three month LIBOR plus 8%	three month LIBOR plus 8%