Segment Reporting (Details) - USD ($) $ in Thousands		3 Months Ended									12 Months Ended
		Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016		Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017		Dec. 31, 2016		Dec. 31, 2015
Financial information relating to reporting segments
Revenue											$ 709,598		$ 568,617		$ 554,557
Royalty Revenue													3,280		6,850
Revenues		$ 214,585	$ 159,919	$ 149,540	$ 185,554	$ 139,204		$ 148,762	$ 156,822	$ 127,109	709,598		571,897		561,407
Costs applicable to sales		121,982	101,559	102,229	114,490	84,903		84,594	81,820	84,058	440,260	[1]	335,375	[1]	403,827	[1]
Amortization		44,722	32,401	30,733	38,693	28,625		26,040	35,653	26,210	146,549		116,528		125,953
Exploration		7,454	9,792	7,813	5,252	5,260		3,706	2,233	1,731	30,311		12,930		11,521
Write-downs											0		4,446		246,625
Other operating expenses											52,552		43,686		48,840
Gain (Loss) on Extinguishment of Debt											(9,342)		(21,365)		15,916
Fair value adjustments, net, pretax											(864)		(11,581)		5,202
Interest expense, net											(16,440)		(36,896)		(44,978)
Other, net											26,643		98		(17,667)
Income and mining tax benefit (expense)											(28,998)		33,247		29,075
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent		14,349	(11,728)	(9,995)	18,299	(10,328)		46,123	8,280	(21,640)	10,925		22,435		(287,811)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent		(6,724)	(4,924)	(960)	364	2,020		23,436	6,217	1,244	(12,244)		32,917		(79,372)
Assets, Net	[2]	1,344,553				1,045,722					1,344,553		1,045,722		1,012,169
Capital expenditures		47,054	$ 28,982	$ 37,107	$ 23,591	28,134		$ 22,626	$ 21,971	$ 21,651	136,734		94,382		88,973
Palmarejo [Member]
Financial information relating to reporting segments
Revenue											274,809		141,273		169,133
Royalty Revenue													0		0
Revenues													141,273		169,133
Costs applicable to sales	[1]										146,176		80,820		138,476
Amortization											73,744		36,599		32,423
Exploration											11,924		5,063		4,533
Write-downs													0		224,507
Other operating expenses											1,263		1,213		1,293
Gain (Loss) on Extinguishment of Debt											0		0		0
Fair value adjustments, net, pretax											0		(5,814)		3,160
Interest expense, net											(487)		1,187		4,269
Other, net											(851)		(12,125)		(10,968)
Income and mining tax benefit (expense)											(24,330)		(45,085)		(37,597)
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent											16,034		43,537		(206,579)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent											0		0		0
Assets, Net	[2]	377,621				436,642					377,621		436,642		406,648
Capital expenditures											29,902		35,810		35,991
Rochester [Member]
Financial information relating to reporting segments
Revenue											152,680		139,945		143,930
Royalty Revenue													0		0
Revenues													139,945		143,930
Costs applicable to sales	[1]										107,921		89,726		103,994
Amortization											22,306		21,838		23,906
Exploration											1,352		841		1,324
Write-downs													0		0
Other operating expenses											3,394		2,801		2,948
Gain (Loss) on Extinguishment of Debt											0		0		0
Fair value adjustments, net, pretax											(864)		(4,133)		818
Interest expense, net											(496)		664		748
Other, net											2,193		(3,859)		(13)
Income and mining tax benefit (expense)											(1,028)		2,785		1,497
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent											17,512		13,298		10,318
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent											0		0		0
Assets, Net	[2]	239,223				219,009					239,223		219,009		190,714
Capital expenditures											40,874		16,446		25,330
Silvertip [Member]
Financial information relating to reporting segments
Revenue											0
Costs applicable to sales	[1]										0
Amortization											0
Exploration											0
Other operating expenses											153
Gain (Loss) on Extinguishment of Debt											0
Fair value adjustments, net, pretax											0
Interest expense, net											(2,212)
Other, net											1,142
Income and mining tax benefit (expense)											(932)
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent											(2,155)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent											0
Assets, Net	[2]	339,369									339,369
Capital expenditures											17,684
Kensington [Member]
Financial information relating to reporting segments
Revenue											154,469		146,593		148,710
Royalty Revenue													0		0
Revenues													146,593		148,710
Costs applicable to sales	[1]										116,096		96,731		105,640
Amortization											36,022		34,787		42,240
Exploration											8,604		3,487		2,596
Write-downs													0		0
Other operating expenses											1,412		1,038		1,301
Gain (Loss) on Extinguishment of Debt											0		0		0
Fair value adjustments, net, pretax											0		0		0
Interest expense, net											(413)		128		218
Other, net											(922)		(25)		7
Income and mining tax benefit (expense)											0		0		0
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent											(9,000)		10,397		(3,278)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent											0		0		0
Assets, Net	[2]	212,588				199,232					212,588		199,232		197,873
Capital expenditures											36,248		36,826		23,834
Wharf [Member]
Financial information relating to reporting segments
Revenue											125,901		136,678		84,052
Royalty Revenue													0		0
Revenues													136,678		84,052
Costs applicable to sales	[1]										69,322		66,379		52,197
Amortization											13,012		20,621		16,378
Exploration											320		2		134
Write-downs													0		0
Other operating expenses											2,468		2,238		1,717
Gain (Loss) on Extinguishment of Debt											0		0		0
Fair value adjustments, net, pretax											0		0		0
Interest expense, net											(66)		69		0
Other, net											172		17		143
Income and mining tax benefit (expense)											(3,936)		4,293		857
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent											36,949		43,093		12,912
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent											0		0		0
Assets, Net	[2]	104,010				105,901					104,010		105,901		113,305
Capital expenditures											8,844		4,812		3,211
Other Mining Properties [Member]
Financial information relating to reporting segments
Revenue											1,739		4,128		8,732
Royalty Revenue													3,280		6,850
Revenues													7,408		15,582
Costs applicable to sales	[1]										745		1,719		3,520
Amortization											1,465		2,683		11,006
Exploration											8,111		3,537		2,934
Write-downs													4,446		22,118
Other operating expenses											43,862		36,396		41,581
Gain (Loss) on Extinguishment of Debt											(9,342)		(21,365)		15,916
Fair value adjustments, net, pretax											0		(1,634)		1,224
Interest expense, net											(12,766)		34,848		39,743
Other, net											24,909		16,090		(6,836)
Income and mining tax benefit (expense)											1,228		4,760		6,168
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent											(48,415)		(87,890)		(101,184)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent											(12,244)		32,917		(79,372)
Assets, Net		$ 71,742				$ 84,938	[2]				71,742		84,938	[2]	103,629	[2]
Capital expenditures											$ 3,182		$ 488		$ 607

[1] Excludes amortization.

[2] Segment assets include receivables, prepaids, inventories, property, plant and equipment, and mineral interest