Hedging Transactions and Derivative Financial Instruments (Effect and Fair Value of Derivative Instruments) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2017
Contracts not designated as hedging instruments \| Other income (expense), net \| Foreign Exchange Contracts
Derivative [Line Items]
Effect of current derivative instruments	$ (60)	$ (312)	$ (291)
Fair Values of Derivative Instruments	118	(312)	(312)
Contracts not designated as hedging instruments \| Other income (expense), net \| Copper Derivatives
Derivative [Line Items]
Effect of current derivative instruments	(363)	71	205
Fair Values of Derivative Instruments	827	1,331	1,331
Contracts designated as hedging instruments \| Other comprehensive income (loss) \| Interest rate swap
Derivative [Line Items]
Effect of current derivative instruments	410	(335)	(515)
Fair Values of Derivative Instruments	$ 1,439	$ (622)	$ (622)

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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- Definition

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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