Note 10 - Restricted Cash and Performance Bonds (Tables)

12 Months Ended

Dec. 31, 2014

Disclosure Text Block Supplement [Abstract]

Schedule of Restricted Cash and Cash Equivalents [Table Text Block]

	December 31, 2014		December 31, 2013
	(in thousands)
Performance bonds totaling $5.7 million for properties in Peru	$	1,559	$	3,459
Performance obligations and commitments for the gas-to-power site		650		650
Secured letters of credit		-		250
$40.0 million secured debt facility		-		1,000
Unsecured performance bond totaling $0.1 million for office lease agreement		-		-
Restricted cash	$	2,209	$	5,359
Current portion of restricted cash as of the end of the period	$	-	$	1,250
Long-term portion of restricted cash as of the end of the period	$	2,209	$	4,109