Benefit Plans - Amounts Recognized in Accumulated Other Comprehensive Income (Loss), Pre-tax (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Retirement Benefits [Abstract]
Net actuarial loss	$ 37,285	$ 15,635
Prior service cost	3,937	4,273
Total	41,222	19,908
Prior service cost	181
Net actuarial loss	782
Prior service cost	324
Net actuarial loss	(19,861)
Net settlement loss	236	$ 260	$ 238
Foreign currency adjustments	(1,298)
Total	$ (19,636)

Defined Benefit Plan, Amortization of Net Actuarial Cost

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Defined Benefit Plan, Foreign Currency Adjustments, Immediate Recognition as Component in Net Periodic Benefit (Cost) Credit

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Defined Benefit Plan, Immediate Recognition as Component in Net Periodic Benefit (Cost) Credit

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Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount, before tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount of gain (loss), recognized immediately as component of net periodic benefit (cost) credit, for change in value of benefit obligation or plan assets from experience different from that assumed, change in actuarial assumption, or consequence of temporarily deviating from substantive plan. Includes, but is not limited to, amount in excess of ten percent of greater of fair value of plan assets or benefit obligation.

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Amount, before tax, of cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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