Derivative Financial Instruments (Details Textual)	3 Months Ended		9 Months Ended
	Sep. 30, 2015 USD ($) oz $ / oz	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) oz $ / oz	Sep. 30, 2014 USD ($)	Dec. 31, 2014 USD ($) oz $ / XAU $ / XAG	Jan. 21, 2009
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Gain (loss) on derivative instruments	$ 5,786,000	$ 16,105,000	$ 3,657,000	$ (3,611,000)
Fair Value Assumptions, Risk Free Interest Rate	19.49%	11.80%
Price per ounce under agreement	$ 412		$ 412
Put Option [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Contract expiration date			3 years
Franco-Nevada warrant [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Fair value liability of the embedded derivative					$ 21,900,000
Realized losses	$ (3,300,000)	$ (5,000,000)	$ (11,000,000)	(16,600,000)
Palmarejo gold production royalty [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Production to be sold, percent						50.00%
Payment made for gold on the end of royalty obligation | oz	4,167		4,167
Remaining ounces under royalty obligation | oz	45,996		45,996
Percentage of Gold Production	50.00%		50.00%
Annual Inflation Compounding Adjustment	1.00%		1.00%
Concentrate Sales Contracts [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Unrealized Gain (Loss) on Derivatives	$ 82,000	(684,000)	$ 373,000	188,000
Gold Put Purchase and Call Sold Options Net [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Derivative Liability, Fair Value					1,039,000
Commodity [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Mark-to-market gains and (losses) on forward foreign exchange contract			900,000
Embedded Derivative Financial Instruments [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Gain (loss) on derivative instruments	2,983,000	8,736,000	1,823,000	(6,560,000)
Derivative Liability, Fair Value					$ 21,912,000
Silver and gold options [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Gain (loss) on derivative instruments	1,051,000	3,081,000	1,238,000	213,000
Mark-to-market gains and (losses) on forward foreign exchange contract	$ (1,051,000)		$ (2,662,000)	$ (1,300,000)
Unrealized Gain (Loss) on Derivatives		$ 3,100,000
Maximum [Member] | Palmarejo gold production royalty [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Payable ounces under royalty obligation | oz	400,000		400,000
Derivative Instruments Settle in Year One [Member] | Gold Put Option [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Weighted Average Strike Price of Put Options | $ / XAU					1,050
Derivative Instruments Settle in Year One [Member] | Silver concentrate sales agreements [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Derivative, Notional Amount	$ (8,234,000)		$ (8,234,000)
Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Outstanding provisionally priced sales consists of silver | oz	562,063		562,063
Derivative Average Price | $ / oz	14.65		14.65
Derivative Instruments Settle in Year One [Member] | Gold concentrates sales agreements [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Derivative, Notional Amount	$ (44,812,000)		$ (44,812,000)
Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Outstanding provisionally priced sales consists of Gold | oz	39,069		39,069
Derivative Average Price | $ / oz	1,147		1,147
Derivative Instruments Settle in Year One [Member] | Kensington Term Facility [Member] | Gold put options purchased [Member] | Put Option [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Weighted Average Strike Price of Put Options | $ / XAU					1,200
Derivative Instruments Settle in Year One [Member] | Kensington Term Facility [Member] | Silver put options purchased [Member] | Put Option [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Weighted Average Strike Price of Put Options | $ / XAG					18.00
Derivative Financial Instruments, Assets [Member] | Gold put options purchased [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Notional ounces | oz					24,000
Derivative Financial Instruments, Assets [Member] | Silver put options purchased [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Notional ounces | oz					1,300,000
Derivative Instruments Settle in Year Two [Member] | Silver concentrate sales agreements [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Derivative, Notional Amount	$ 0		$ 0
Notional ounces | oz	0		0
Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Derivative Average Price | $ / oz	0		0
Derivative Instruments Settle in Year Two [Member] | Gold concentrates sales agreements [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Derivative, Notional Amount	$ 0		$ 0
Notional ounces | oz	0		0
Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Derivative Average Price | $ / oz	0		0
Derivative Instruments Settle in Year Two [Member] | Silver Put Options Sold [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Weighted Average Strike Price of Put Options | $ / XAG					16.00
Derivative Instruments Settle Thereafter [Member] | Silver concentrate sales agreements [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Derivative, Notional Amount	$ 0		$ 0
Notional ounces | oz	0		0
Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Derivative Average Price | $ / oz	0		0
Derivative Instruments Settle Thereafter [Member] | Gold concentrates sales agreements [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Derivative, Notional Amount	$ 0		$ 0
Notional ounces | oz	0		0
Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Derivative Average Price | $ / oz	0		0
Prepaid Expenses and Other Current Assets [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Fair value of the contract	$ 120,000		$ 120,000		$ 3,925,000
Prepaid Expenses and Other Current Assets [Member] | Gold Put Purchase and Call Sold Options Net [Member]
Additional Derivative Financial Instruments and Fair Value of Financial Instruments (Textual) [Abstract]
Fair value of the contract					$ 3,882,000