Impairment of Long-Lived Assets and Restaurant Closure Charges (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 16, 2020	Jun. 18, 2019	Dec. 31, 2019
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 400
Accretion	12	$ 0
Ending Balance	400
Noncurrent portion of restaurant closure liability	249		$ 308
Restaurant closure liabilities	199		$ 129
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	(1)	(192)
Adjustments to estimates based on current activity	0	118
Ending Balance	$ 448	$ 118

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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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