Balance Sheet Information - Equipment and Leasehold Improvements, Net (Detail) - USD ($) $ in Thousands	Jun. 26, 2015	Dec. 26, 2014
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 41,219	$ 35,502
Accumulated depreciation	(26,369)	(24,661)
Total	14,850	10,841
Computer equipment and software [Member]
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	9,639	9,299
Furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	2,708	2,582
Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	13,534	10,774
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Equipment and leasehold improvements, gross	$ 15,338	$ 12,847

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

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-Section 50

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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

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+ 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 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC

-Name Regulation S-X (SX)

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