Note 19 - Business Segments (Tables)

12 Months Ended

Dec. 31, 2018

Notes Tables

Schedule of Segment Reporting Information, by Segment [Table Text Block]

	Electricity		Product		Other			Consolidated
	(Dollars in thousands)
Year Ended December 31, 2018:
Revenues from external customers:
United States (1)	$	305,962	$	14,999	$	7,645		$	328,606
Foreign (2)		203,917		186,744		—			390,661
Net revenues from external customers		509,879		201,743		7,645			719,267
Intersegment revenues		—		48,817		—			48,817
Depreciation and amortization expense		126,181		4,311		1,741			132,233
Operating income (loss)		155,546		38,083		(8,519	)		185,110
Segment assets at period end (3) (*)		2,896,938		156,942		67,470			3,121,350
Expenditures for long-lived assets		219,803		9,993		28,725			258,521
* Including unconsolidated investments		71,983		—		—			71,983
Year Ended December 31, 2017:
Net revenues from external customers	$	465,593	$	224,483	$	2,736		$	692,812
Intersegment revenues		—		109,040		—			109,040
Depreciation and amortization expense		109,928		3,470		1,748			115,146
Operating income		157,613		50,543		(3,138	)		205,018
Segment assets at period end (3) (*)		2,457,514		115,713		50,637			2,623,864
Expenditures for long-lived assets		252,581		6,653		—			259,234
* Including unconsolidated investments		34,084		—		—			34,084
Year Ended December 31, 2016 :
Net revenues from external customers	$	436,292	$	226,299	$	—			662,591
Intersegment revenues		—		56,075		—			56,075
Depreciation and amortization expense		102,698		3,279		—			105,977
Operating income		126,828		75,054		—			201,882
Segment assets at period end		2,204,444		257,125		—			2,461,569
Expenditures for long-lived assets		147,211		4,719		—			151,930

Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block]

	Year Ended December 31,
	2018			2017			2016
	(Dollars in thousands)
Revenues:
Total segment revenues	$	719,267		$	692,812		$	662,591
Intersegment revenues		48,817			109,040			56,075
Elimination of intersegment revenues		(48,817	)		(109,040	)		(56,075	)
Total consolidated revenues	$	719,267		$	692,812		$	662,591
Operating income:
Operating income	$	185,110		$	205,018		$	201,882
Interest income		974			988			971
Interest expense, net		(70,924	)		(54,142	)		(67,389	)
Foreign currency translation and transaction losses		(4,761	)		2,654			(5,534	)
Income attributable to sale of equity interest		19,003			17,878			16,503
Other non-operating income, net		7,779			(1,666	)		(5,345	)
Total consolidated income before income taxes and equity in income of investees	$	137,181		$	170,730		$	141,088

Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas [Table Text Block]

	Year Ended December 31,
	2018		2017		2016
	(Dollars in thousands)
Revenues from external customers attributable to: (1)
United States	$	328,606	$	301,132	$	307,025
Indonesia		4,379		28,968		100,856
Kenya		119,094		110,243		109,270
Turkey		168,699		125,166		46,270
Chile		980		8,895		58,032
Guatemala		27,975		27,991		30,086
New Zealand		10,451		33,395		—
Other foreign countries		59,083		57,022		11,052
Consolidated total	$	719,267	$	692,812	$	662,591

Schedule of Disclosure on Geographic Areas, Long-Lived Assets in Individual Foreign Countries by Country [Table Text Block]

	Year Ended December 31,
	2018		2017		2016
	(Dollars in thousands)
Long-lived assets (primarily power plants and related assets) located in:
United States	$	1,696,439	$	1,510,986	$	1,414,523
Kenya		301,956		340,970		327,157
Other foreign countries		222,872		281,333		199,559
Consolidated total	$	2,221,267	$	2,133,289	$	1,941,239

Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block]

	Year Ended December 31,
	2018				2017				2016
	Revenues		%		Revenues		%		Revenues		%
	(Dollars in thousands)				(Dollars in thousands)				(Dollars in thousands)
Southern California Public Power (1)	$	109,208		15.2	$	70,100		10.1	$	67,566		10.2
Sierra Pacific Power Company and Nevada Power Company (1)(2)		116,149		16.1		125,424		18.1		127,226		19.2
Hyundai (3)		4,379		0.6		28,968		4.2		100,856		15.2
KPLC (1)		119,094		16.6		110,243		15.9		109,270		16.5