Derivative Instruments - Additional Information (Detail) - USD ($)	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Derivative [Line Items]
Anticipated foreign-denominated sales hedge	$ 17,088,000
(Losses) gains on foreign exchange transactions included in other income (expense)	$ (1,064,000)	$ 1,173,000
Copper Purchases [Member]
Derivative [Line Items]
Percentage of anticipated purchases hedged	46.00%
Time period for hedged purchases	12 months
Copper Purchases [Member] \| Cash Flow Hedges [Member]
Derivative [Line Items]
Anticipated purchases, hedged	$ 2,350,000
Aluminum Purchases [Member]
Derivative [Line Items]
Percentage of anticipated purchases hedged	56.00%
Time period for hedged purchases	6 months
Aluminum Purchases [Member] \| Cash Flow Hedges [Member]
Derivative [Line Items]
Anticipated purchases, hedged	$ 435,000
Foreign Currency Sales Contract - Fair Value Hedges [Member]
Derivative [Line Items]
Fair value of assets held as collateral related to forward exchange contracts	5,624,000
Foreign Currency Sales Contract - Fair Value Hedges [Member] \| Standby Letters of Credit [Member]
Derivative [Line Items]
Fair value of assets held as collateral related to forward exchange contracts	$ 5,000,000

Fair value of assets provided as collateral.

No definition available.

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- Definition

Percentage of anticipated requirements which are covered by cash flow hedges.

+ References

No definition available.

+ Details

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- Definition

Period covered by cash flow hedges.

+ References

No definition available.

+ Details

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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- Definition

Amount of the hedged item as of the balance sheet date related to the derivative. For example, the hedged balance on a debt instrument.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6450222&loc=d3e30840-110895

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64836518&loc=d3e30700-110894

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=64836518&loc=d3e30690-110894

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- Details

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- Details

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- Details

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- Details

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