Fair Value Measurements (Details Textual)						9 Months Ended
Sep. 30, 2014 Convertible Senior Notes Due March 2028 [Member]	Dec. 31, 2013 Convertible Senior Notes Due March 2028 [Member]	Sep. 30, 2014 Senior Notes due 2021 [Member]	Dec. 31, 2013 Senior Notes due 2021 [Member]	Jan. 29, 2013 Senior Notes due 2021 [Member]	Sep. 30, 2014 Palmarejo [Member]	Sep. 30, 2014 Rochester [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Expected Royalty Duration						1.7	4.3
Debt Instrument, Interest Rate, Stated Percentage	3.25%	3.25%	7.875%	7.875%	7.875%

Contractual interest rate for funds borrowed, under the debt agreement.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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