Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 28, 2018	Dec. 29, 2017	Dec. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation and related expenses	$ 16,458	$ 15,558	$ 12,794
General and administrative expenses	535	597	539
Total stock-based compensation expense	16,993	16,155	13,333
Income tax benefit	4,467	6,331	5,214
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation and related expenses	15,561	14,809	12,225
General and administrative expenses	535	597	539
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation and related expenses	$ 897	$ 749	$ 569

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&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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