Derivative Instruments - Additional Information (Detail)	12 Months Ended
Dec. 31, 2019 USD ($) Customer Derivative	Dec. 31, 2018 USD ($)
Derivative [Line Items]
Anticipated foreign-denominated sales hedge	$ 18,060,000
Percentage of purchase commitments covering anticipated natural gas usage	75.00%
Purchase commitment amount of anticipated natural gas usage	$ 1,368,000
Number of subsidiaries purchased commitments for natural gas usage \| Customer	1
Purchase commitments covering period anticipated usage, Description	for one of its subsidiaries
Number of derivative instruments holds for trading purposes \| Derivative	0
(Losses) gains on foreign exchange transactions included in other income (expense)	$ (1,081,000)	$ (1,480,000)
Natural Gas Purchases [Member]
Derivative [Line Items]
Purchase of natural gas	$ 682,000	$ 1,285,000
Copper Purchases [Member]
Derivative [Line Items]
Percentage of anticipated purchases hedged	49.00%
Time period for hedged purchases	10 months
Copper Purchases [Member] \| Cash Flow Hedges [Member]
Derivative [Line Items]
Anticipated purchases, hedged	$ 2,287,000
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	$ 480,000

Number of derivative instruments holds for trading purposes.

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- Definition

Number of subsidiaries who have committed to purchase a portion of their anticipated natural gas requirements in advance.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

Percentage of anticipated requirements which are covered by purchase commitments.

+ References

No definition available.

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Period covered by cash flow hedges.

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- Definition

Dollar value of anticipated natural gas requirements which are covered by purchase commitments.

+ References

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- Definition

Purchase commitments covering period anticipated usage description.

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- Definition

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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-Paragraph 2
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- Definition

Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

+ References

No definition available.

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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.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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