Mining Properties (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Mining Properties
Operational mining properties:	$ 657,498	$ 641,305
Accumulated depletion	(340,459)	(315,541)
Operational mining properties, net	317,039	325,764
Mineral interest	1,760,834	1,753,129
Accumulated depletion	(349,206)	(327,392)
Mineral interest, net	1,411,628	1,425,737
Total mining properties	1,728,667	1,751,501
Palmarejo [Member]
Mining Properties
Operational mining properties:	158,631	151,845
Accumulated depletion	(116,097)	(110,143)
Operational mining properties, net	42,534	41,702
Mineral interest	1,146,572	1,146,572
Accumulated depletion	(318,214)	(300,187)
Mineral interest, net	828,358	846,385
Total mining properties	870,892	888,087
San Bartolome [Member]
Mining Properties
Operational mining properties:	70,764	70,761
Accumulated depletion	(24,091)	(22,236)
Operational mining properties, net	46,673	48,525
Mineral interest	26,643	26,643
Accumulated depletion	(9,434)	(8,759)
Mineral interest, net	17,209	17,884
Total mining properties	63,882	66,409
Kensington [Member]
Mining Properties
Operational mining properties:	275,660	268,351
Accumulated depletion	(92,162)	(80,032)
Operational mining properties, net	183,498	188,319
Mineral interest	0	0
Accumulated depletion	0	0
Mineral interest, net	0	0
Total mining properties	183,498	188,319
Rochester [Member]
Mining Properties
Operational mining properties:	152,443	150,348
Accumulated depletion	(108,109)	(103,130)
Operational mining properties, net	44,334	47,218
Mineral interest	0	0
Accumulated depletion	0	0
Mineral interest, net	0	0
Total mining properties	44,334	47,218
Endeavor [Member]
Mining Properties
Operational mining properties:	0	0
Accumulated depletion	0	0
Operational mining properties, net	0	0
Mineral interest	408,352	408,352
Accumulated depletion	0	0
Mineral interest, net	408,352	408,352
Total mining properties	408,352	408,352
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	93,429
Accumulated depletion	0	0
Mineral interest, net	93,429	93,429
Total mining properties	93,429	93,429
Other Mining Properties [Member]
Mining Properties
Operational mining properties:	0	0
Accumulated depletion	0	0
Operational mining properties, net	0	0
Mineral interest	85,838	78,133
Accumulated depletion	(21,558)	(18,446)
Mineral interest, net	64,280	59,687
Total mining properties	$ 64,280	$ 59,687