Segment Information, Reconciliation of Total Segment Profits to Consolidated Totals (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Reconciliation of total segment profits to the Company's consolidated totals [Abstract]
Net income	$ 6,835	$ 1,958	$ 42,654	$ 28,532
Net loss attributable to non-controlling interest in subsidiaries	(3)	(334)	(119)	(669)
Net income attributable to controlling interest	6,838	2,292	42,773	29,201
Reportable Segments [Member]
Reconciliation of total segment profits to the Company's consolidated totals [Abstract]
Net income	6,704	994	42,021	28,564
Intersegment Eliminations [Member]
Reconciliation of total segment profits to the Company's consolidated totals [Abstract]
Net income	$ 131	$ 964	$ 633	$ (32)