Inventory and Ore on Leach Pads (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Inventory Disclosure [Abstract]
Inventory, Finished Goods, Net of Reserves	$ 17,373	$ 16,165
Other Inventory, Net of Reserves	19,122	21,908
Inventory, Supplies, Net of Reserves	42,102	43,638
Inventory	78,597	81,711
Ore on Leach Pad, Current	72,703	67,329
Ore on leach pads, noncurrent	49,294	44,582
Inventory, Ore Stockpiles on Leach Pads, Gross	121,997	111,911
Inventory and Ore on Leach Pads	$ 200,594	$ 193,622