Hedging Transactions and Derivative Financial Instruments (Effect and Fair Value of Derivative Instruments) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Contracts not designated as hedging instruments | Other income (expense), net | Foreign Exchange Contracts
Derivative [Line Items]
Effect of current derivative instruments	$ (198)	$ 29	$ (382)	$ 29
Fair Values of Derivative Instruments	(382)	29	(382)	29
Contracts not designated as hedging instruments | Other income (expense), net | Copper Derivatives
Derivative [Line Items]
Effect of current derivative instruments	474	(94)	578	(163)
Fair Values of Derivative Instruments	1,534	$ 490	1,534	$ 490
Contracts designated as hedging instruments | Other comprehensive income (loss) | Interest rate swap
Derivative [Line Items]
Effect of current derivative instruments	100		(415)
Fair Values of Derivative Instruments	$ (638)		$ (638)