Benefit Plans - Change in Plan Assets (Detail) - Pension Plans - 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	$ 276,699	$ 256,168
Actual return on plan assets	40,680	29,549
Employer contributions	16,250	4,900
Benefits paid	(13,930)	(13,918)
Ending balance - plan assets at fair value	$ 319,699	$ 276,699

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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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.

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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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