Note 9 - Investment in Ecuador Property (Details) - Carrying Value of Investment Property (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Carrying Value of Investment Property [Abstract]
Investment in Ecuador property, net	$ 501bpz_InvestmentPropertyNet	$ 534bpz_InvestmentPropertyNet

This item represents the net carrying amount of the entity's investment interest in an oil and gas property accounted for under the cost method, net of accumulated amortization. As the entity has not been able to receive timely information to allow it to proportionately consolidate the minority non-operated working interest owned by its consolidated subsidiary, SMC Ecuador Inc., the entity accounts for this investment under the cost method and records its share of cash received or paid attributable to this investment as other income or expense and amortizes its investment into income over the remaining term of the license agreement, which expires in May 2016.

No definition available.

Name:	bpz_InvestmentPropertyNet
Namespace Prefix:	bpz_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant