Impairment of Long-Lived Assets and Restaurant Closure Charges (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 24, 2020	Mar. 26, 2019
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 400
Accretion	8
Ending Balance	400
Closure of 12 Underperforming Restaurants [Member] \| Contract Termination [Member]
Restructuring Reserve [Roll Forward]
Beginning Balance	437	$ 2,092
Reclassified to operating lease right-of-use assets	0	(1,900)
Cash payments	0	(192)
Adjustments to estimates based on current activity	0	118
Ending Balance	$ 445	$ 118

Reclassification Of Liability To Operating Lease, Right-Of-Use Asset

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Amount recognized for the passage of time, typically for liabilities, that have been discounted to their net present values. Excludes accretion associated with asset retirement obligations.

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Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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