Note 24 - Quarterly Financial Information (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2019

Notes Tables

Quarterly Financial Information [Table Text Block]

	Three Months Ended
	Mar. 31, 2018			June 30, 2018			Sept. 30, 2018			Dec. 31, 2018			Mar. 31, 2019			June 30, 2019			Sept. 30, 2019			Dec. 31, 2019
	(Dollars in thousands, except per share amounts)
Revenues:
Electricity	$	132,489		$	122,179		$	116,891		$	138,320		$	142,908		$	129,079		$	123,978		$	144,368
Product		48,672			54,915			48,439			49,717			52,128			52,030			43,037			43,814
Energy storage and management services		2,862			1,205			1,150			2,428			4,002			2,956			3,484			4,260
Total revenues		184,023			178,299			166,480			190,465			199,038			184,065			170,499			192,442
Cost of revenues:
Electricity		73,482			81,236			79,845			63,692			77,543			73,775			80,124			81,393
Product		33,726			37,573			35,669			33,729			42,106			41,316			31,073			31,479
Energy storage and management services		3,443			2,028			2,174			2,235			5,210			3,827			3,807			5,068
Total cost of revenues		110,651			120,837			117,688			99,656			124,859			118,918			115,004			117,940
Gross profit		73,372			57,462			48,792			90,809			74,179			65,147			55,495			74,502
Operating expenses:
Research and development expenses		1,108			1,251			706			1,118			900			810			1,062			1,875
Selling and marketing expenses		3,699			3,712			8,578			3,813			3,865			3,276			3,783			4,123
General and administrative expenses		13,849			15,866			13,606			4,429			15,689			14,181			11,931			14,032
Impairment charge		—			—			—			13,464			—			—			—			—
Write-off of unsuccessful exploration activities		123			—			—			3			—			—			—			—
Operating income		54,593			36,633			25,902			67,982			53,725			46,880			38,719			54,472
Other income (expense):
Interest income		113			189			214			458			293			420			482			320
Interest expense, net		(14,344	)		(15,846	)		(18,700	)		(22,034	)		(21,223	)		(21,517	)		(20,076	)		(17,568	)
Derivatives and foreign currency transaction gains (losses)		(1,599	)		(529	)		(383	)		(2,250	)		472			19			205			(72	)
Income attributable to sale of tax benefits		7,361			3,556			4,066			4,020			7,764			4,637			4,056			4,415
Other non-operating income (expense), net		(20	)		7,373			309			117			91			1,027			244			(482	)
Income from operations before income tax and equity in earnings (losses) of investees		46,104			31,376			11,408			48,293			41,122			31,466			23,630			41,085
Income tax (provision)		26,942			(29,105	)		(1,184	)		(31,386	)		(14,039	)		3,529			(9,626	)		(25,477	)
Equity in earnings (losses) of investees, net		1,210			388			(117	)		6,182			1,047			1,202			1,085			(1,481	)
Net income		74,256			2,659			10,107			23,089			28,130			36,197			15,089			14,127
Net loss (income) attributable to noncontrolling interest		(4,748	)		(3,002	)		474			(4,869	)		(2,184	)		(2,259	)		516			(1,521	)
Net income (loss) attributable to the Company's stockholders	$	69,508		$	(343	)	$	10,581		$	18,220		$	25,946		$	33,938		$	15,605		$	12,606
Earnings (loss) per share attributable to the Company's stockholders
Basic:
Net income	$	1.37		$	(0.01	)	$	0.21		$	0.36		$	0.51		$	0.67		$	0.31		$	0.25
Diluted:
Net income	$	1.36		$	(0.01	)	$	0.21		$	0.36		$	0.51		$	0.66		$	0.30		$	0.24
Weighted average number of shares used in computation of earnings per share attributable to the Company's stockholders:
Basic		50,614			50,623			50,645			50,691			50,709			50,800			50,933			51,017
Diluted		51,051			50,958			50,963			50,936			51,012			51,094			51,334			51,511