Mining Properties (Tables)

3 Months Ended

Mar. 31, 2018

Mining Properties [Abstract]

Mining Properties

Mining properties consist of the following (in thousands):

March 31, 2018	Palmarejo			Rochester			Silvertip		Kensington			Wharf				La Preciosa		Other			Total
Mine development	$	220,141		$	194,390		$	70,626	$	307,996		$	40,688			$	—	$	—		$	833,841
Accumulated amortization	(151,102		)	(146,245		)	—		(182,555		)	(16,456		)		—		—			(496,358		)
	69,039			48,145			70,626		125,441			24,232				—		—			337,483
Mineral interests	629,303			—			245,116		—			45,837				49,085		7,102			976,443
Accumulated amortization	(445,327		)	—			—		—			(24,655		)	—	—		(123		)	(470,105		)
	183,976			—			245,116		—			21,182				49,085		6,979			506,338
Mining properties, net	$	253,015		$	48,145		$	315,742	$	125,441		$	45,414			$	49,085	$	6,979		$	843,821

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