Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 29, 2017	Mar. 30, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, options outstanding (shares)	2,191,728
Common stock, options vested (shares)	1,746,501
Common stock, options unvested (shares)	445,227
Stock options exercised (shares)	0	0
Number of options granted at fair market value (shares)	0	0
Unrecognized compensation expense	$ 1,100
Unrecognized compensation expense, recognition period	2 years 9 months 7 days
Stock-based compensation expense (less than $0.1 million in 2016)	$ 141	$ 11
Premium Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, options outstanding (shares)	1,569,436
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unvested restricted shares outstanding (shares)	30,185

Unrecognized cost of unvested share-based compensation awards.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Number of non-vested options outstanding.

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Number of options vested.

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Number of share options (or share units) exercised during the current period.

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