Mining Properties (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Mining Properties
Operational mining properties:	$ 735,233	$ 674,636
Accumulated depletion	(293,971)	(247,562)
Operational mining properties, net	441,262	427,074
Mineral interest	2,233,037	1,822,493
Accumulated depletion	(308,300)	(257,758)
Mineral interest, net	1,924,737	1,564,735
Total mining properties	2,365,999	1,991,809
Palmarejo [Member]
Mining Properties
Operational mining properties:	170,789	155,722
Accumulated depletion	(101,687)	(82,037)
Operational mining properties, net	69,102	73,685
Mineral interest	1,660,580	1,658,389
Accumulated depletion	(282,339)	(235,795)
Mineral interest, net	1,378,241	1,422,594
Total mining properties	1,447,343	1,496,279
San Bartolome [Member]
Mining Properties
Operational mining properties:	70,371	70,322
Accumulated depletion	(21,270)	(18,439)
Operational mining properties, net	49,101	51,883
Mineral interest	26,643	26,642
Accumulated depletion	(8,398)	(7,338)
Mineral interest, net	18,245	19,304
Total mining properties	67,346	71,187
Kensington [Member]
Mining Properties
Operational mining properties:	345,447	333,619
Accumulated depletion	(68,909)	(46,649)
Operational mining properties, net	276,538	286,970
Mineral interest	0	0
Accumulated depletion	0	0
Mineral interest, net	0	0
Total mining properties	276,538	286,970
Rochester [Member]
Mining Properties
Operational mining properties:	148,626	114,973
Accumulated depletion	(102,105)	(100,437)
Operational mining properties, net	46,521	14,536
Mineral interest	0	0
Accumulated depletion	0	0
Mineral interest, net	0	0
Total mining properties	46,521	14,536
Martha [Member]
Mining Properties
Operational mining properties:	0
Accumulated depletion	0
Operational mining properties, net	0
Mineral interest	44,033
Accumulated depletion	(17,563)
Mineral interest, net	26,470
Total mining properties	26,470
Endeavor [Member]
Mining Properties
Operational mining properties:	0	0
Accumulated depletion	0	0
Operational mining properties, net	0	0
Mineral interest	408,352	44,033
Accumulated depletion	0	(14,625)
Mineral interest, net	408,352	29,408
Total mining properties	408,352	29,408
Joaquin [Member]
Mining Properties
Operational mining properties:	0	0
Accumulated depletion	0	0
Operational mining properties, net	0	0
Mineral interest	93,429	93,429
Accumulated depletion	0	0
Mineral interest, net	93,429	93,429
Total mining properties	$ 93,429	$ 93,429