Benefit Plans - Reconciliation of Plan Assets Fair Value (Detail) - Postretirement Benefits - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 29, 2019
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance - plan assets at fair value	$ 0	$ 0
Employer contributions	2,431	2,460
Plan participants’ contributions	753	750
Benefits paid	(3,184)	(3,296)
Medicare Part D subsidy reimbursement	0	86
Ending balance - plan assets at fair value	$ 0	$ 0

Amount of contributions received by defined benefit plan from participant which increase benefit obligation.

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- Definition

Amount, before benefit payment, of receipt from prescription drug subsidy which increases benefit obligation of defined benefit postretirement plan.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References

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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.

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- Definition

Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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