Impairment Of Long-Lived Assets And Other Lease Charges Closed Restaurant Reserve Activity (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 29, 2019	Dec. 31, 2017
Restructuring Reserve [Roll Forward]
Closed-restaurant reserve, beginning of the period	$ 1,352
Provisions for restaurant closures	42	$ 249
Changes in estimates of accrued costs	293	(147)
Payments, net	(446)	(889)
Other adjustments, including the effect of discounting future obligations	685	111
Closed-restaurant reserve, end of the period	$ 1,926	$ 2,028

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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Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

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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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No definition available.

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Amount of increase (decrease) in the restructuring reserve related to foreign currency translation (gain) loss and other increases (decreases).

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