Debt (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015 USD ($) oz	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) oz	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Debt Instrument [Line Items]
Percentage of Actual Gold Production	50.00%
Long term debt and capital lease obligations
Current	$ 9,121		$ 9,121		$ 17,498
Non-current	538,589		538,589		451,048
Interest expenses incurred for various debt instruments
Interest Paid on Convertible Notes due 2028	6	$ 43	43	$ 86
Interest Paid on Senior Notes due 2021	8,523	8,859	17,085	15,323
Interest paid on short-term credit agreement	326	0	326	0
Interest paid on term loan due 2020	148	0	148	0
San Bartolomé Line of Credit	293	0	565	0
Line of Credit Facility, Commitment Fee Amount	0	0	0	179
Write off revolver costs, interest expense	0	0	0	3,035
Interest Paid on Capital Leases	272	333	570	392
Accretion of Franco Nevada royalty obligation	1,771	2,898	3,802	6,094
Debt Issuance Cost	508	420	913	918
Amortization of debt issuance costs	(104)	(108)	(209)	(144)
Capitalized interest	(1,009)	(135)	(1,744)	(518)
Total interest expense, net of capitalized interest	10,734	$ 12,310	21,499	$ 25,365
San Bartolome Letter of Credit Facility [Member]
Long term debt and capital lease obligations
Non-current	$ 8,655		$ 8,655		$ 10,304
3.25% Convertible Senior Notes due March 2028 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.25%		3.25%		3.25%
Long term debt and capital lease obligations
Debt Instrument, Face Amount					$ 0
Senior Notes due 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.875%		7.875%		7.875%
Long term debt and capital lease obligations
Non-current	$ 426,234		$ 426,234		$ 427,603
Palmarejo gold production royalty [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	30.50%		30.50%
Capital Lease Obligations [Member]
Long term debt and capital lease obligations
Non-current	$ 9,315		$ 9,315		13,141
Palmarejo gold production royalty [Member]
Debt Instrument [Line Items]
Minimum Obligation Paid in Monthly Payments | oz	4,167		4,167
Annual Inflation Compounding Adjustment	1.00%		1.00%
Short Term Credit Agreement [Member]
Long term debt and capital lease obligations
Current	$ 1,000		$ 1,000		0
Non-current	$ 93,673		$ 93,673		0
3.25% Convertible Senior Notes due March 2028 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.25%		3.25%
Long term debt and capital lease obligations
Current	$ 0		$ 0		5,334
Senior Notes due 2021 [Member]
Long term debt and capital lease obligations
Current	0		0		0
Capital Lease Obligations [Member]
Long term debt and capital lease obligations
Current	7,635		7,635		7,683
San Bartolome Letter of Credit Facility [Member]
Long term debt and capital lease obligations
Current	$ 486		$ 486		$ 4,481