Note 13 - Discontinued Operations (Details) - Summary of Financial Information Related to Discontinued Operations (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2013
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total income from discontinued operations	$ 4,480	$ 5,311
Selling and Marketing Expense [Member] | Momotombo Power Plant [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Selling and marketing expenses:	(130)	(192)
Momotombo Power Plant [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues - electricity	2,062	4,866
Cost of revenues - electricity	(1,020)	(2,869)
Gross margin	1,042	1,997
General and administrative expenses:	(74)	(140)
Operating income:	838	1,665
Income from discontinued operations before income taxes	4,480	5,311
Income tax provision	(363)	(614)
Total income from discontinued operations	$ 4,117	$ 4,697