Information for Each Reportable Segment (Detail) - USD ($) $ in Thousands	3 Months Ended
Apr. 01, 2017	Apr. 02, 2016
Segment Reporting Information [Line Items]
Total segment net revenues	$ 30,388	$ 13,664
Income (loss) from operations	2,091	(6,316)
Interest income and other income (expense), net	110	37
Income (loss) before income taxes	2,201	(6,279)
Thin-film Equipment Segment
Segment Reporting Information [Line Items]
Total segment net revenues	21,484	5,580
Photonics
Segment Reporting Information [Line Items]
Total segment net revenues	8,904	8,084
Operating Segments
Segment Reporting Information [Line Items]
Income (loss) from operations	3,324	(5,038)
Operating Segments \| Thin-film Equipment Segment
Segment Reporting Information [Line Items]
Income (loss) from operations	1,859	(5,445)
Operating Segments \| Photonics
Segment Reporting Information [Line Items]
Income (loss) from operations	1,465	407
Unallocated Amount to Segment
Segment Reporting Information [Line Items]
Unallocated costs	$ (1,233)	$ (1,278)

Unallocated costs.

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- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68072869&loc=d3e41242-110953

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(10))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(15))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(8))
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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The net amount of nonoperating interest income (expense).

+ References

No definition available.

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The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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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.

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No definition available.

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