Mining Properties (Tables)

9 Months Ended

Sep. 30, 2018

Mining Properties [Abstract]

Mining Properties

Mining properties consist of the following (in thousands):

September 30, 2018	Palmarejo			Rochester			Silvertip			Kensington			Wharf			La Preciosa		Other			Total
Mine development	$	233,562		$	196,143		$	105,320		$	322,901		$	41,498		$	—	$	—		$	899,424
Accumulated amortization	(159,120		)	(149,729		)	(389		)	(191,026		)	(17,811		)	—		—			(518,075		)
	74,442			46,414			104,931			131,875			23,687			—		—			381,349
Mineral interests	629,303			—			245,116			—			45,837			49,085		5,171			974,512
Accumulated amortization	(463,565		)	—			(988		)	—			(25,843		)	—		(422		)	(490,818		)
	165,738			—			244,128			—			19,994			49,085		4,749			483,694
Mining properties, net	$	240,180		$	46,414		$	349,059		$	131,875		$	43,681		$	49,085	$	4,749		$	865,043

December 31, 2017	Palmarejo			Rochester			Silvertip		Kensington			Wharf			La Preciosa		Total
Mine development	$	214,383		$	193,881		$	57,214	$	298,749		$	40,618		$	—	$	804,845
Accumulated amortization	(146,598		)	(144,390		)	—		(178,632		)	(15,748		)	—		(485,368		)
	67,785			49,491			57,214		120,117			24,870			—		319,477
Mineral interests	629,303			—			245,116		—			45,837			49,085		969,341
Accumulated amortization	(435,215		)	—			—		—			(24,034		)	—		(459,249		)
	194,088			—			245,116		—			21,803			49,085		510,092
Mining properties, net	$	261,873		$	49,491		$	302,330	$	120,117		$	46,673		$	49,085	$	829,569