Derivative Financial Instruments and Fair Value of Financial Instruments (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments	$ (23,113)	$ (5,302)
Fair value adjustments, net	(22,560)	(6,399)
Concentrate Sales Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Sales of Metals	1,336	(1,349)
Forward foreign exchange contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Production costs applicable to sales	(783)	252
Fair value adjustments	2,690	1,005
Gold lease facility [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments	0	(132)
Forward gold contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments	0	35
Silver Ounces Receivables [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments	359	831
Palmarejo gold production royalty [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments	(25,611)	(6,343)
Put and call options [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments	$ (551)	$ (698)