Derivative Financial Instruments (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments, net	$ (11,436)	$ 17,796
Fair value adjustments, net	(10,808)	16,669
Mexican peso forward purchase contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments, net	968	738
Concentrate Sales Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Sales of Metals	879	(1,755)
Forward foreign exchange contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Production costs applicable to sales	(924)	627
Fair value adjustments, net	968	(860)
Forward Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments, net	0	(1,598)
Palmarejo gold production royalty [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments, net	(10,237)	14,429
Put and call options [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value adjustments, net	$ (1,494)	$ 4,228