Derivative Instruments (Company's Outstanding Commodity Derivatives) (Details)	3 Months Ended
	Mar. 31, 2016 oz $ / oz
Second Quarter 2016 [Member] | Platinum [Member]
Derivative [Line Items]
Ounces | oz	21,120
Average Price/Ounce | $ / oz	915
Second Quarter 2016 [Member] | Palladium [Member]
Derivative [Line Items]
Ounces | oz	39,807
Average Price/Ounce | $ / oz	532
Second Quarter 2016 [Member] | Rhodium [Member]
Derivative [Line Items]
Ounces | oz	4,608
Average Price/Ounce | $ / oz	653
Third Quarter 2016 [Member] | Platinum [Member]
Derivative [Line Items]
Ounces | oz	4,203
Average Price/Ounce | $ / oz	963
Third Quarter 2016 [Member] | Palladium [Member]
Derivative [Line Items]
Ounces | oz	4,072
Average Price/Ounce | $ / oz	548
Third Quarter 2016 [Member] | Rhodium [Member]
Derivative [Line Items]
Ounces | oz	1,536
Average Price/Ounce | $ / oz	684