Debt (Details) (USD $)	3 Months Ended
	Mar. 31, 2014 oz	Mar. 31, 2013	Dec. 31, 2013	Mar. 31, 2014 3.25% Convertible Senior Notes due March 2028 [Member]	Mar. 31, 2014 Senior Notes due 2021 [Member]	Mar. 12, 2014 Senior Notes due 2021 [Member]	Dec. 31, 2013 Senior Notes due 2021 [Member]	Jan. 29, 2013 Senior Notes due 2021 [Member]	Mar. 31, 2014 Palmarejo gold production royalty [Member]	Mar. 31, 2014 Capital Lease Obligations [Member]	Dec. 31, 2013 Capital Lease Obligations [Member]	Mar. 31, 2014 Palmarejo gold production royalty [Member] oz	Mar. 31, 2014 Maximum [Member] Palmarejo gold production royalty [Member] oz	Mar. 31, 2014 Convertible Senior Notes Due March 2028 [Member]	Dec. 31, 2013 Convertible Senior Notes Due March 2028 [Member]	Feb. 12, 2013 Convertible Senior Notes Due March 2028 [Member]	Mar. 31, 2014 Senior Notes due Two Thousand Twenty One [Member]	Dec. 31, 2013 Senior Notes due Two Thousand Twenty One [Member]	Mar. 31, 2014 Capital Lease Obligations [Member]	Dec. 31, 2013 Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Debt Instrument, Convertible, Carrying Amount of Equity Component				$ 10,900,000
Debt Instrument, Interest Rate, Effective Percentage									30.00%
Royalty Guarantees, Commitments, Ounces of Gold													400,000
Minimum Obligation Paid in Monthly Payments												4,167
Annual Inflation Compounding Adjustment												1.00%
Percentage of Actual Gold Production	50.00%
Derivative Average Gold Price in Excess of Minimum Contractual Deduction Rate	408
Long term debt and capital lease obligations
Current	8,095,000		2,505,000											5,334,000	0	48,700,000	0	0	2,761,000	2,505,000
Debt Instrument, Face Amount					450,000,000	150,000,000		300,000,000						0	5,334,000
Non-current	456,152,000		306,130,000		452,964,000		300,000,000			3,188,000	796,000
Payment of Royalty on Ounces of Gold	275,898
Base Average Gold Price in Excess of Minimum Contractual Deduction Rate	400
Interest expenses incurred for various debt instruments
Interest Paid on Senior Notes due 2021	6,464,000	4,134,000
Interest Paid on Convertible Notes due 2028	43,000	337,000
Line of Credit Facility, Commitment Fee Amount	179,000	125,000
Write off revolver costs, interest expense	3,035,000	0
Interest Paid on Capital Leases	59,000	168,000
Interest Expense	0	197,000
Accretion of Franco Nevada royalty obligation	3,196,000	4,062,000
Amortization of debt issuance costs	498,000	525,000
Accretion of debt discount	(36,000)	577,000
Capitalized interest	(384,000)	(393,000)
Total interest expense, net of capitalized interest	$ 13,054,000	$ 9,732,000