Other, Net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Other Income and Expenses [Abstract]
Foreign exchange gain (loss)	$ 1,000	$ (5,656)	$ 2,442	$ (5,819)
Gain (Loss) on Disposition of Other Assets	513	3,126	(1,552)	4,211
Gain on sale of the Joaquin project	0	0	21,138	0
Gain (loss) on the sale of royalties	2,332	0	2,332	0
Impairment of equity securities	(305)	(20)	(426)	(20)
Other	596	693	1,341	1,085
Other, net	$ 4,136	$ (1,857)	$ 25,275	$ (543)