Mining Properties (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Mining Properties
Operational mining properties:	$ 686,052	$ 649,905
Accumulated depletion	(258,978)	(203,416)
Operational mining properties, net	427,074	446,489
Mineral interest	1,822,493	1,729,064
Accumulated depletion	(257,758)	(174,668)
Mineral interest, net	1,564,735	1,554,396
Non-producing and developmental properties(B)	142	142
Total mining properties	1,991,951	2,001,027
Palmarejo [Member]
Mining Properties
Operational mining properties:	155,722	134,296
Accumulated depletion	(82,037)	(53,060)
Operational mining properties, net	73,685	81,236
Mineral interest	1,658,389	1,658,389
Accumulated depletion	(235,795)	(158,627)
Mineral interest, net	1,422,594	1,499,762
Non-producing and developmental properties(B)	0	0
Total mining properties	1,496,279	1,580,998
San Bartolome [Member]
Mining Properties
Operational mining properties:	70,322	68,684
Accumulated depletion	(18,439)	(14,989)
Operational mining properties, net	51,883	53,695
Mineral interest	26,642	26,642
Accumulated depletion	(7,338)	(6,007)
Mineral interest, net	19,304	20,635
Non-producing and developmental properties(B)	0	0
Total mining properties	71,187	74,330
Kensington [Member]
Mining Properties
Operational mining properties:	333,619	321,456
Accumulated depletion	(46,649)	(27,160)
Operational mining properties, net	286,970	294,296
Mineral interest	0	0
Accumulated depletion	0	0
Mineral interest, net	0	0
Non-producing and developmental properties(B)	0	0
Total mining properties	286,970	294,296
Rochester [Member]
Mining Properties
Operational mining properties:	114,973	112,826
Accumulated depletion	(100,437)	(97,834)
Operational mining properties, net	14,536	14,992
Mineral interest	0	0
Accumulated depletion	0	0
Mineral interest, net	0	0
Non-producing and developmental properties(B)	0	0
Total mining properties	14,536	14,992
Martha [Member]
Mining Properties
Operational mining properties:	11,416	12,643
Accumulated depletion	(11,416)	(10,373)
Operational mining properties, net	0	2,270
Mineral interest	0	0
Accumulated depletion	0	0
Mineral interest, net	0	0
Non-producing and developmental properties(B)	0	0
Total mining properties	0	2,270
Endeavor [Member]
Mining Properties
Operational mining properties:	0	0
Accumulated depletion	0	0
Operational mining properties, net	0	0
Mineral interest	44,033	44,033
Accumulated depletion	(14,625)	(10,034)
Mineral interest, net	29,408	33,999
Non-producing and developmental properties(B)	0	0
Total mining properties	29,408	33,999
Joaquin Project - Argentina [Member]
Mining Properties
Operational mining properties:	0	0
Accumulated depletion	0	0
Operational mining properties, net	0	0
Mineral interest	93,429
Accumulated depletion		0
Mineral interest, net	93,429	0
Total mining properties	93,429	0
Other Mining Properties [Member]
Mining Properties
Operational mining properties:	0	0
Accumulated depletion	0	0
Operational mining properties, net	0	0
Mineral interest	0	0
Accumulated depletion	0	0
Mineral interest, net	0	0
Non-producing and developmental properties(B)	142	142
Total mining properties	$ 142	$ 142