Employee Benefit Plans - pre-tax change in the benefit obligation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 26, 2019	Dec. 27, 2018
Employee Benefit Plans
Net actuarial loss (gain)	$ 7,317	$ (2,633)
Amortization of the net actuarial loss	(499)	(685)
Amortization of the prior service credit	63	64
Total	$ 6,881	$ (3,254)

Amount of before tax gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

No definition available.

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- Definition

Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

+ References

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- References

No definition available.

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- Definition

Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

+ References

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- Definition

Amount, after tax, of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

+ References

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