Financial Instruments - Commodity Contracts (Details) - Commodity $ in Thousands	3 Months Ended
	Mar. 31, 2020 USD ($) oz lb T
Silver, Ounces
Derivative [Line Items]
Amount | oz	135,354
Notional Value	$ 1,955
Gold, Ounces | Not Designated as Hedging Instrument
Derivative [Line Items]
Amount | oz	1,941
Notional Value	$ 3,126
Palladium, Ounces | Not Designated as Hedging Instrument
Derivative [Line Items]
Amount | oz	573
Notional Value	$ 1,299
Copper, Pounds
Derivative [Line Items]
Notional Value	$ 565
Copper, Pounds | Not Designated as Hedging Instrument
Derivative [Line Items]
Amount | lb	215,000
Tin, Metric Tons | Not Designated as Hedging Instrument
Derivative [Line Items]
Amount | T	30
Notional Value	$ 462