Mining Properties (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Mining Properties
Operational mining properties:	$ 615,844	$ 557,799
Accumulated depletion	(396,067)	(368,410)
Operational mining properties, net	219,777	189,389
Mineral interest	1,029,620	679,429
Accumulated depletion	(384,513)	(367,626)
Mineral interest, net	645,107	311,803
Total mining properties	864,884	501,192
Palmarejo [Member]
Mining Properties
Operational mining properties:	154,514	137,821
Accumulated depletion	(127,458)	(121,906)
Operational mining properties, net	27,056	15,915
Mineral interest	821,913	521,349
Accumulated depletion	(340,433)	(332,032)
Mineral interest, net	481,480	189,317
Total mining properties	508,536	205,232
San Bartolome [Member]
Mining Properties
Operational mining properties:	49,419	49,305
Accumulated depletion	(28,592)	(26,106)
Operational mining properties, net	20,827	23,199
Mineral interest	17,560	17,560
Accumulated depletion	(10,762)	(10,143)
Mineral interest, net	6,798	7,417
Total mining properties	27,625	30,616
Kensington [Member]
Mining Properties
Operational mining properties:	224,586	217,138
Accumulated depletion	(118,415)	(106,865)
Operational mining properties, net	106,171	110,273
Mineral interest	0	0
Accumulated depletion	0	0
Mineral interest, net	0	0
Total mining properties	106,171	110,273
Rochester [Member]
Mining Properties
Operational mining properties:	155,269	153,535
Accumulated depletion	(120,031)	(113,533)
Operational mining properties, net	35,238	40,002
Mineral interest	0	0
Accumulated depletion	0	0
Mineral interest, net	0	0
Total mining properties	35,238	40,002
Wharf [Member]
Mining Properties
Operational mining properties:	32,056
Accumulated depletion	(1,571)
Operational mining properties, net	30,485
Mineral interest	49,601
Accumulated depletion	(3,097)
Mineral interest, net	46,504
Total mining properties	76,989
Endeavor [Member]
Mining Properties
Operational mining properties:	0	0
Accumulated depletion	0	0
Operational mining properties, net	0	0
Mineral interest	49,085	49,059
Accumulated depletion	0	0
Mineral interest, net	49,085	49,059
Total mining properties	49,085	49,059
Joaquin Project - Argentina [Member]
Mining Properties
Operational mining properties:	0	0
Accumulated depletion	0	0
Operational mining properties, net	0	0
Mineral interest	10,000	10,000
Accumulated depletion	0	0
Mineral interest, net	10,000	10,000
Total mining properties	10,000	10,000
Other Mining Properties [Member]
Mining Properties
Operational mining properties:	$ 0	0
Accumulated depletion		0
Operational mining properties, net	$ 0	0
Mineral interest	81,461	81,461
Accumulated depletion	(30,221)	(25,451)
Mineral interest, net	51,240	56,010
Total mining properties	$ 51,240	$ 56,010