Restaurant Closure and Other Related Charges - Restaurant Closure Liability Activity (Details) $ in Thousands	4 Months Ended	12 Months Ended
Dec. 29, 2015 location	Dec. 31, 2019 USD ($)	Jan. 01, 2019 USD ($)	Jan. 02, 2018 USD ($)
Restructuring Reserve [Roll Forward]
Closure liability at beginning of period		$ 2,400
Charges for accretion in current period		0	$ 449	$ 379
Closure liability at end of period		400	2,400
Closure of 12 Underperforming Restaurants [Member]
Restructuring Reserve [Roll Forward]
Closure liability at beginning of period		2,092	1,611	1,773
Adjustments to estimate based on current activity		508	747
Charges for accretion in current period		(1,900)	61	70
Cash payments		(263)	(327)	(376)
Adjustment to estimates based on current activity				144
Closure liability at end of period		$ 437	$ 2,092	$ 1,611
Number of underperforming locations \| location	12

Number of Underperforming Restaurant Locations

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Restructuring Reserve, Reclassification of Lease Related Liabilities

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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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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to 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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