Derivative Financial Instruments and Fair Value of Financial Instruments (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments	$ 66,754	$ 16,039	$ 84,550	$ (7,074)
Fair value adjustments, net	66,290	14,010	82,957	(8,549)
Concentrate Sales Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Sales of Metals	(667)	(877)	(2,422)	459
Forward foreign exchange contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Production costs applicable to sales	203	(1,151)	830	(1,934)
Fair value adjustments	1,598	0	0	0
Forward foreign exchange contracts MXN peso [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments	(2,260)	83
Gold Lease Facility [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments			(1,522)	2,773
Silver Ounces Receivables [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments	0	(337)	0	22
Palmarejo gold production royalty [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments	61,066	14,105	75,494	(11,505)
Put and call options [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments	$ 6,350	$ 2,187	$ 10,577	$ 1,636