Mining Properties (Details Textual) (USD $) In Thousands, unless otherwise specified	1 Months Ended	3 Months Ended		4 Months Ended		1 Months Ended
	Mar. 31, 2006 oz	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2008 oz	Dec. 31, 2012	Apr. 30, 2002 Martha [Member]	May 23, 2005 Endeavor [Member] oz
Property, Plant and Equipment (Textual) [Abstract]
Acquisition of interest in mine						100.00%
Impairment of Long-Lived Assets Held-for-use		$ 119	$ 0
Assets		$ 3,423,682			$ 3,221,401
Quantity of acquired silver production and reserves							17,700,000
Mining Properties (Textual) [Abstract]
Cumulative ounces of silver received by CDE Australia				4,300,000
Current ore reserve payable ounces based on current metallurgical recovery and current smelter contract terms				4,300,000
Silver production and reserves payable ounces	20,000,000