Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 29, 2017	Dec. 30, 2016	Jan. 01, 2016
Share-Based Compensation Arrangement By Share-Based Payment Award [Line Items]
Compensation and related expenses	$ 15,558	$ 12,794	$ 12,459
General and administrative expenses	597	539	500
Total stock-based compensation expense	16,155	13,333	12,959
Income tax benefit	6,331	5,214	5,068
Restricted Stock [Member]
Share-Based Compensation Arrangement By Share-Based Payment Award [Line Items]
Compensation and related expenses	14,809	12,225	11,907
General and administrative expenses	597	539	500
Employee Stock Option [Member]
Share-Based Compensation Arrangement By Share-Based Payment Award [Line Items]
Compensation and related expenses	$ 749	$ 569	$ 552

Income tax benefit associated with stock-based compensation.

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- Definition

Amount of general and administrative expense classified as other.

+ 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 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

Amount of labor-related expenses classified as other.

+ References

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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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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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