Benefit Plans - Funded Status, Pension Plans (Detail) - Pension Plans - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 29, 2019	Dec. 30, 2018
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ (368,245)	$ (332,304)	$ (278,957)
Plan assets at fair value	319,699	276,699	$ 256,168
Net funded status	$ (48,546)	$ (55,605)

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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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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- Definition

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.

+ References

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- Definition

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.

+ References

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