Condensed Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 25, 2020
Statement of Comprehensive Income [Abstract]
Tax effect of minimum pension liability adjustment	$ 10	$ 6
Changes in fair value of cash flow derivatives, tax	763	(11,795)
Reclassification of cash flow derivatives to interest expense, tax	255	86
Reclassification of unrealized losses related to derivatives to interest expense, tax	$ 31	$ 0

Other Comprehensive Income (Loss), Reclassification Of Unrealized Gains (Losses), Tax

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e640-108580

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- Definition

Amount of tax expense (benefit) for reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

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Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

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-Topic 220
-SubTopic 10
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-Section 45
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