Information for Each Reportable Segment (Detail) - USD ($) $ in Thousands	3 Months Ended
Apr. 02, 2016	Apr. 04, 2015
Segment Reporting Information [Line Items]
Total segment net revenues	$ 13,664	$ 19,885
Operating loss	(6,316)	(2,939)
Interest income and other, net	37	79
Loss before income taxes	(6,279)	(2,860)
Thin-film Equipment Segment
Segment Reporting Information [Line Items]
Total segment net revenues	5,580	10,628
Photonics
Segment Reporting Information [Line Items]
Total segment net revenues	8,084	9,257
Operating Segments
Segment Reporting Information [Line Items]
Operating loss	(5,038)	(1,820)
Operating Segments \| Thin-film Equipment Segment
Segment Reporting Information [Line Items]
Operating loss	(5,445)	(3,297)
Operating Segments \| Photonics
Segment Reporting Information [Line Items]
Operating loss	407	1,477
Unallocated Amount to Segment
Segment Reporting Information [Line Items]
Unallocated costs	$ (1,278)	$ (1,119)

Unallocated costs.

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- Definition

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and 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=51673353&loc=d3e41242-110953

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 10
-Article 5

+ Details

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- Definition

The net amount of nonoperating interest income (expense).

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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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=26872669&loc=d3e20235-122688

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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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