Mining Properties (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Mining Properties
Operational mining properties:	$ 872,693	$ 804,845
Accumulated depletion	(506,651)	(485,368)
Operational mining properties, net	366,042	319,477
Mineral interest	976,443	969,341
Accumulated depletion	(481,106)	(459,249)
Mineral interest, net	495,337	510,092
Total mining properties	861,379	829,569
Palmarejo [Member]
Mining Properties
Operational mining properties:	227,048	214,383
Accumulated depletion	(155,239)	(146,598)
Operational mining properties, net	71,809	67,785
Mineral interest	629,303	629,303
Accumulated depletion	(455,346)	(435,215)
Mineral interest, net	173,957	194,088
Total mining properties	245,766	261,873
Rochester [Member]
Mining Properties
Operational mining properties:	196,182	193,881
Accumulated depletion	(147,968)	(144,390)
Operational mining properties, net	48,214	49,491
Mineral interest	0	0
Accumulated depletion	0	0
Mineral interest, net	0	0
Total mining properties	48,214	49,491
Silvertip [Member]
Mining Properties
Operational mining properties:	93,325	57,214
Accumulated depletion	0	0
Operational mining properties, net	93,325	57,214
Mineral interest	245,116	245,116
Accumulated depletion	0	0
Mineral interest, net	245,116	245,116
Total mining properties	338,441	302,330
Kensington [Member]
Mining Properties
Operational mining properties:	315,097	298,749
Accumulated depletion	(186,204)	(178,632)
Operational mining properties, net	128,893	120,117
Mineral interest	0	0
Accumulated depletion	0	0
Mineral interest, net	0	0
Total mining properties	128,893	120,117
Wharf [Member]
Mining Properties
Operational mining properties:	41,041	40,618
Accumulated depletion	(17,240)	(15,748)
Operational mining properties, net	23,801	24,870
Mineral interest	45,837	45,837
Accumulated depletion	(25,343)	(24,034)
Mineral interest, net	20,494	21,803
Total mining properties	44,295	46,673
La Preciosa [Member]
Mining Properties
Operational mining properties:	0	0
Accumulated depletion	0	0
Operational mining properties, net	0	0
Mineral interest	49,085	49,085
Accumulated depletion	0	0
Mineral interest, net	49,085	49,085
Total mining properties	49,085	$ 49,085
Other Mining Properties [Member]
Mining Properties
Operational mining properties:	0
Accumulated depletion	0
Operational mining properties, net	0
Mineral interest	7,102
Accumulated depletion	(417)
Mineral interest, net	6,685
Total mining properties	$ 6,685