Funded Status of Local 1199 Pension Plan and Retiree Medical Plan (Detail) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Pension Benefit Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of plan assets at end of fiscal year	$ 3,946	$ 3,322
Benefit obligation at end of fiscal year	6,680	5,357
Unfunded Status	(2,734)	(2,035)
Retiree Medical Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Benefit obligation at end of fiscal year	888	731
Unfunded Status	$ (888)	$ (731)

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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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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