Debt - Additional Information (Detail)	6 Months Ended
Jun. 30, 2018 USD ($)
Debt Instrument [Line Items]
Maximum percentage of stock of non US subsidiaries pledge to secure obligation	66.00%
Federal Funds Rate \| Minimum
Debt Instrument [Line Items]
Interest rate	0.50%
Federal Funds Rate \| Maximum
Debt Instrument [Line Items]
Interest rate	1.91%
London Interbank Offered Rate
Debt Instrument [Line Items]
Interest rate	2.09%
Revolving Note (U.S. Dollar)
Debt Instrument [Line Items]
Undrawn borrowing capacity	$ 250,934,000
Debt maturity date	Mar. 17, 2021
United State Bank Of America Credit Facility
Debt Instrument [Line Items]
Interest rate	5.00%
Euro Currency Rate Loans \| Minimum
Debt Instrument [Line Items]
Interest rate	0.00%
Euro Currency Rate Loans \| Minimum \| Amended Credit Agreement
Debt Instrument [Line Items]
Interest rate	1.25%
Euro Currency Rate Loans \| Maximum
Debt Instrument [Line Items]
Interest rate	1.00%
Euro Currency Rate Loans \| Maximum \| Amended Credit Agreement
Debt Instrument [Line Items]
Interest rate	2.00%
Base Rate Loans \| Minimum \| Amended Credit Agreement
Debt Instrument [Line Items]
Interest rate	0.25%
Base Rate Loans \| Maximum \| Amended Credit Agreement
Debt Instrument [Line Items]
Interest rate	1.00%
DEG Loan
Debt Instrument [Line Items]
Semi-annual principal payments earliest date	2015-03
Semi-annual principal payments latest date	2019-09
DEG Vietnam Loan
Debt Instrument [Line Items]
Semi-annual principal payments earliest date	2017-11
Semi-annual principal payments latest date	2023-05
Revolving Credit Facility \| Revolving Note (U.S. Dollar)
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 350,000,000

Debt instrument maturity month and year range end.

No definition available.

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- Definition

Debt instrument maturity month and year range start.

+ References

No definition available.

+ Details

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- Definition

Percentage of stock interest on subsidiaries pledge to secure obligation.

+ 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

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The effective interest rate during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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