Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
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-Section 50
-Paragraph 1
-Subparagraph (a)
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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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COMPONENTS OF THE COMPANY'S CONSOLIDATED BALANCE SHEETS Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 290,005	$ 257,437
Depreciation	18,374	16,812	$ 16,464
Accumulated depreciation	$ 178,300	$ 162,141
Property and Equipment [Member] \| Geographic Concentration Risk [Member]
Property, Plant and Equipment [Line Items]
Concentration Risk, Percentage	10.00%	10.00%	10.00%
Property and Equipment [Member] \| Geographic Concentration Risk [Member] \| United States of America
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 159,500	$ 155,100	$ 150,100
Property and Equipment [Member] \| Geographic Concentration Risk [Member] \| THAILAND
Property, Plant and Equipment [Line Items]
Concentration Risk, Percentage	12.00%	12.00%	12.00%
Land
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 20,288	$ 20,288
Construction-in-progress
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	15,353	6,880
Building and improvements
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	52,655	52,156
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	151,269	132,162
Computer software and hardware and office furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 50,440	$ 45,951
Minimum [Member] \| Building and improvements
Property, Plant and Equipment [Line Items]
Property and Equipment, Useful Life	4 years
Minimum [Member] \| Machinery and equipment
Property, Plant and Equipment [Line Items]
Property and Equipment, Useful Life	2 years
Minimum [Member] \| Computer software and hardware and office furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and Equipment, Useful Life	4 years
Maximum [Member] \| Building and improvements
Property, Plant and Equipment [Line Items]
Property and Equipment, Useful Life	40 years
Maximum [Member] \| Machinery and equipment
Property, Plant and Equipment [Line Items]
Property and Equipment, Useful Life	8 years
Maximum [Member] \| Computer software and hardware and office furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and Equipment, Useful Life	7 years