Note 7 - Property, Plant and Equipment and Construction-In-Process (Details) (USD $)	12 Months Ended												12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Power Plants [Member] Kenya [Member]	Dec. 31, 2012 Power Plants [Member] Kenya [Member]	Dec. 31, 2013 Momotombo Power Plant [Member]	Dec. 31, 2013 Orzunil I de Electricidad, Limitada [Member]	Dec. 31, 2012 Orzunil I de Electricidad, Limitada [Member]	Dec. 31, 2013 Ortitlan, Limitada [Member]	Dec. 31, 2012 Ortitlan, Limitada [Member]	Dec. 13, 2013 Foreign Countries [Member]	Dec. 31, 2012 Foreign Countries [Member]	Dec. 31, 2013 Kenya [Member]	Dec. 31, 2012 Kenya [Member]
Note 7 - Property, Plant and Equipment and Construction-In-Process (Details) [Line Items]
Depreciation	$ 91,791,000	$ 89,876,000	$ 89,600,000
Depreciation Net of Amortization of Cash Grant	4,330,000	5,553,000
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	601,065,000	544,670,000				35,396,000
Property Plant and Equipment Including Construction in Progress	1,316,597,000	1,287,635,000		338,517,000	272,050,000		18,846,000	21,628,000	52,272,000	43,360,000	424,567,000	361,379,000
Property Plant and Equipment Cash Grant	127,675,000	117,320,000
Construction in Progress Costs Incurred													$ 98,065,000	$ 167,344,000
Royalty Rate	12.00%