Segment Reporting (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Long Lived Assets
Long Lived Assets in Entity's Country of Domicile	$ 786,908	$ 787,986
Revenues
Revenue	662,497	639,236	$ 632,526
Revenues	665,777	646,086	635,742
UNITED STATES
Long Lived Assets
Long Lived Assets in Entity's Country of Domicile	338,897	336,210
Revenues
Revenue	423,216	376,692	260,728
Mexico
Long Lived Assets
Long Lived Assets in Entity's Country of Domicile	397,697	390,694
Revenues
Revenue	142,198	171,911	245,493
BOLIVIA
Long Lived Assets
Long Lived Assets in Entity's Country of Domicile	31,539	35,201
Revenues
Revenue	93,880	84,679	117,749
AUSTRALIA
Long Lived Assets
Long Lived Assets in Entity's Country of Domicile	2,983	5,952
Revenues
Revenue	4,128	8,732	10,046
ARGENTINA
Long Lived Assets
Long Lived Assets in Entity's Country of Domicile	10,228	10,871
Other Foreign Countries [Member]
Long Lived Assets
Long Lived Assets in Entity's Country of Domicile	5,564	9,058
Revenues
Revenue	$ 2,355	$ 4,072	$ 1,726