Income Taxes (Schedule of Unrecognized Tax Benefits) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 26, 2020	Dec. 28, 2019
Income Taxes [Abstract]
Unrecognized tax benefits at beginning of year	$ 6,612	$ 6,405
Increases based on tax positions related to the current year	1,725	1,769
Additions for tax positions of prior year	0	0
Reductions for tax positions of prior years	0	0
Settlements	0	0
Expiration of the statute of limitations for assessment of taxes	0	(1,562)
Unrecognized tax benefits at end of year	$ 8,337	$ 6,612

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Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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