Debt (Detail)	6 Months Ended
Jun. 30, 2018 USD ($) bank
Line of Credit Facility [Line Items]
Number of banks to which Company is party to a Credit Agreement \| bank	2
Calculated maximum borrowings	$ 150,000,000.0
Available increase in borrowings under Credit Agreement	100,000,000.0
Outstanding borrowings	0
Letters of credit outstanding	1,300,000
Calculated maximum borrowing amount available in current year	$ 148,700,000
Credit Agreement \| Minimum
Line of Credit Facility [Line Items]
Percentage of commitment fee	0.15%
Credit Agreement \| Maximum
Line of Credit Facility [Line Items]
Percentage of commitment fee	0.30%
Credit Agreement \| Credit Agreement Interest Rate Option One \| Minimum \| London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate (as a percent)	0.875%
Credit Agreement \| Credit Agreement Interest Rate Option One \| Maximum \| London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate (as a percent)	1.75%
Credit Agreement \| Credit Agreement Interest Rate Option Two \| London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate (as a percent)	1.00%
Credit Agreement \| Credit Agreement Interest Rate Option Two \| Prime Rate
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate (as a percent)	1.00%
Credit Agreement \| Credit Agreement Interest Rate Option Two \| Minimum \| Base Rate
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate (as a percent)	0.00%
Credit Agreement \| Credit Agreement Interest Rate Option Two \| Maximum \| Federal Funds Rate
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate (as a percent)	0.50%
Credit Agreement \| Credit Agreement Interest Rate Option Two \| Maximum \| Base Rate
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate (as a percent)	0.25%

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- 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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Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Definition

An Accordion, also called an Option, gives the Borrower the right to increase a credit facility up to a certain amount as defined in the credit agreement without getting further approval from existing lenders. The incremental dollars may be provided by the existing Lenders or new Lenders.

+ References

No definition available.

+ Details

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Namespace Prefix:	wire_
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Balance Type:	credit
Period Type:	duration

- Definition

Number of lender banks in credit agreement.

+ References

No definition available.

+ Details

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