Accumulated Other Comprehensive (Income) Loss - Components of Accumulated Other Comprehensive (Income) Loss, Net of Tax (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 26, 2020	Dec. 31, 2019
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	$ (1,264,026)	$ (361,888)
Balance	(1,264,746)	(1,264,026)
Accumulated Foreign Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	564	1,273
Net current period other comprehensive (income) loss	(5,043)	(709)
Reclassifications	0	0
Balance	(4,479)	564
Accumulated Net Unrealized Gain (Loss) on Available-For-Sale Marketable Securities [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	34	(10)
Net current period other comprehensive (income) loss	(123)	44
Reclassifications	0	0
Balance	(89)	34
Accumulated Other Comprehensive Income/ (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Balance	598	1,263
Net current period other comprehensive (income) loss	(5,166)	(665)
Reclassifications	0	0
Balance	$ (4,568)	$ 598

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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