Segment Reporting (Details Textual) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Segment Reporting (Textual) [Abstract]
Total Revenue	$ 343,575	$ 118,564	$ 774,289	$ 307,871
Silver [Member]
Segment Reporting (Textual) [Abstract]
Total Revenue	233,700	73,300	505,000	206,600
Gold [Member]
Segment Reporting (Textual) [Abstract]
Total Revenue	$ 109,900	$ 45,300	$ 269,300	$ 101,300

Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 5

-Section 03

-Paragraph 1

Reference 2: 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))

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

Name:	us-gaap_SalesRevenueGoodsNet
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration