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, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Contracts not designated as hedging instruments \| Other income (expense), net \| Foreign Exchange Contracts
Derivative [Line Items]
Effect of current derivative instruments	$ 29	$ (198)	$ (95)	$ (382)
Fair Values of Derivative Instruments	342	(382)	342	(382)
Contracts not designated as hedging instruments \| Other income (expense), net \| Copper Derivatives
Derivative [Line Items]
Effect of current derivative instruments	(453)	474	(1,637)	578
Fair Values of Derivative Instruments	631	1,534	631	1,534
Contracts designated as hedging instruments \| Other comprehensive income (loss) \| Interest rate swap
Derivative [Line Items]
Effect of current derivative instruments	270	100	1,669	(415)
Fair Values of Derivative Instruments	$ 1,710	$ (638)	$ 1,710	$ (638)

Fair value of the assets less the liabilities of a derivative or group of derivatives.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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