CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 26, 2019	Dec. 27, 2018	Dec. 28, 2017
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Change in unrealized gain on available for sale investments, net of tax benefit	$ 0	$ 0	$ 9
Pension gain (loss) arising during period, net of tax effect (benefit)	(1,833)	708	(1,685)
Amortization of the net actuarial loss and prior service credit related to the pension, net of tax effect	109	167	142
Fair market value adjustment of interest rate swap, net of tax benefit	300	115	0
Reclassification adjustment on interest rate swap included in interest expense, net of tax effect	$ 44	$ 59	$ 0

Amount of tax expense (benefit) for increase (decrease) to other comprehensive income from settlement and curtailment gain (loss) of defined benefit plan.

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-Publisher FASB
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-SubTopic 10
-Section 45
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Amount of tax (expense) benefit of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

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Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount, before reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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