Selected Quarterly Financial and Earnings Data (Unaudited) (Details) $ in Thousands	3 Months Ended	12 Months Ended
Jan. 03, 2021 USD ($)	Sep. 27, 2020 USD ($)	Jun. 28, 2020 USD ($) restaurant	Mar. 29, 2020 USD ($)	Dec. 29, 2019 USD ($)	Sep. 29, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jan. 03, 2021 USD ($) restaurant	Dec. 29, 2019 USD ($)	Dec. 30, 2018 USD ($)
Quarterly Financial Information Disclosure [Abstract]
Restaurants Acquired \| restaurant			233						44
Acquisition-related costs	$ 2,800	$ 2,800	$ 2,600	$ 2,600
Impairment and other lease charges	$ 5,000	$ 2,000	$ 2,900	$ 2,900	$ 1,800	$ 500	$ 400	$ 900	$ 12,778	$ 3,564	$ 3,685
Number of Restaurants	1,074	1,088	1,092	1,093	1,101	1,088	1,081	845	1,074	1,101
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount	$ 12,900								$ 13,138	$ 0	0
Impairment charges									$ 8,200	$ 1,700	$ 2,700

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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The number of businesses acquired by the entity during the period.

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Amount of restructuring charges, remediation cost, and asset impairment loss.

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