Income Tax - Activity Related to Company's Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	9 Months Ended
Sep. 23, 2016	Sep. 25, 2015
Income Tax Disclosure [Abstract]
Balance as of the beginning of period	$ 337	$ 356
Increase related to current year tax positions	61
Expiration of the statute of limitations for the assessment of taxes	(24)	(26)
Balance as of the end of period	$ 374	$ 330

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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=SL6600010-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Unrecognized Tax Benefit
-URI http://asc.fasb.org/extlink&oid=6527854

+ Details

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- Definition

Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

+ Details

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- Definition

Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

+ References

+ Details

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