Condensed Consolidated Statements of Operations and Comprehensive Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Revenues:
Electricity	$ 107,868	$ 89,953
Product	43,726	30,278
Total revenues	151,594	120,231
Cost of revenues:
Electricity	63,686	55,581
Product	24,035	20,625
Total cost of revenues	87,721	76,206
Gross margin	63,873	44,025
Operating expenses:
Research and development expenses	349	363
Selling and marketing expenses	3,675	3,433
General and administrative expenses	8,749	10,204
Write-off of unsuccessful exploration activities	557	174
Operating income	50,543	29,851
Other income (expense):
Interest income	320	9
Interest expense, net	(16,023)	(17,828)
Foreign currency translation and transaction gains (losses)	1,962	(1,366)
Income attributable to sale of tax benefits	4,398	5,552
Other non-operating income (expense), net	191	283
and equity in losses of investees	41,391	16,501
Income tax (provision) benefit	(9,509)	(5,459)
Equity in losses of investees, net	(937)	(775)
Income from continuing operations	30,945	10,267
Net income attributable to noncontrolling interest	(1,674)	(235)
Net income attributable to the Company's stockholders	29,271	10,032
Comprehensive income:
Net income	30,945	10,267
Other comprehensive income (loss), net of related taxes:
Change in unrealized gains or losses in respect of the Company's share in derivatives instruments of unconsolidated investment	(3,179)	(3,296)
Loss in respect of derivative instruments designated for cash flow hedge	21	23
Amortization of unrealized gains in respect of derivative instruments designated for cash flow hedge	(24)	(30)
Comprehensive income	27,763	6,964
Comprehensive income attributable to noncontrolling interest	(1,674)	(235)
Comprehensive income attributable to the Company's stockholders	$ 26,089	$ 6,729
Earnings per share attributable to the Company's stockholders:
Net income (in dollars per share)	$ 0.60	$ 0.21
Net income (in dollars per share)	$ 0.59	$ 0.21
Weighted average number of shares used in computation of earnings per share attributable to the Company's stockholders:
Basic (in shares)	49,173	47,244
Diluted (in shares)	49,782	48,079
Common Stock, Dividends, Per Share, Declared	$ 0.31	$ 0.08