Employee Benefit Plans - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Profit Sharing Plan
Defined Contribution Plan Disclosure [Line Items]
Employee benefit plans, contribution cost	$ 1,313	$ 1,317	$ 1,195
Profit Sharing Plan \| Management
Defined Contribution Plan Disclosure [Line Items]
Employee benefit plans, contribution cost	$ 3,691	$ 2,913	$ 2,382
EPSP annualized interest rate, added percentage above prime rate	2.00%
Maximum \| Profit Sharing Plan \| Management
Defined Contribution Plan Disclosure [Line Items]
EPSP annualized interest rate cap	15.00%
Savings Plan
Defined Contribution Plan Disclosure [Line Items]
Employee benefit plans, employer contribution percentage	6.00%	6.00%	6.00%
Employee benefit plans, contribution cost	$ 2,901	$ 3,405	$ 2,676
Savings Plan \| Maximum
Defined Contribution Plan Disclosure [Line Items]
Employee benefit plans, employer matching contribution percentage	50.00%	50.00%	50.00%

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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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

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

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Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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- Definition

Applicable margin rate.

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