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Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-Subparagraph (b)
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Aggregate revenue from the sale of minerals and related products, and from rendering services such as exploration, development, mining, processing and providing mining support activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(a),(d))
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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Segment Reporting (Details 2) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
Segment Reporting (Details 2) - USD ($) $ in Thousands	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Long Lived Assets
Long Lived Assets in Entity's Country of Domicile	$ 781,836		$ 781,836		$ 787,986
Revenues
Revenue	176,386	$ 160,932	503,219	$ 476,391
Revenues	176,247	162,552	506,641	481,770
United States [Member]
Long Lived Assets
Long Lived Assets in Entity's Country of Domicile	327,448		327,448		336,210
Revenues
Revenue	117,425	93,091	317,315	280,340
Mexico [Member]
Long Lived Assets
Long Lived Assets in Entity's Country of Domicile	403,185		403,185		390,694
Revenues
Revenue	30,663	50,170	109,674	129,753
BOLIVIA
Long Lived Assets
Long Lived Assets in Entity's Country of Domicile	32,361		32,361		35,201
Revenues
Revenue	27,485	17,391	73,948	62,304
Australia [Member]
Long Lived Assets
Long Lived Assets in Entity's Country of Domicile	3,102		3,102		5,952
Revenues
Revenue	812	1,264	3,207	6,292
ARGENTINA
Long Lived Assets
Long Lived Assets in Entity's Country of Domicile	10,227		10,227		10,871
Other Foreign Countries [Member]
Long Lived Assets
Long Lived Assets in Entity's Country of Domicile	5,513		5,513		$ 9,058
Revenues
Revenue	$ (138)	$ 636	$ 2,497	$ 3,081