Details of Finite-lived Intangible Assets by Segment (Detail) - USD ($) $ in Thousands	Apr. 01, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Finite Lived, Gross Carrying Amount	$ 8,387
Accumulated Amortization	(6,342)	$ (6,129)
Finite Lived, Net Carrying Amount	2,045	$ 2,258
Thin-film Equipment Segment
Finite-Lived Intangible Assets [Line Items]
Finite Lived, Gross Carrying Amount	7,172
Accumulated Amortization	(5,318)
Finite Lived, Net Carrying Amount	1,854
Photonics
Finite-Lived Intangible Assets [Line Items]
Finite Lived, Gross Carrying Amount	1,215
Accumulated Amortization	(1,024)
Finite Lived, Net Carrying Amount	$ 191

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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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

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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