Restaurant Impairments, Closure Costs and Asset Disposals - Narrative (Details) $ in Millions	12 Months Ended
Dec. 29, 2020 USD ($) restaurant	Dec. 31, 2019 USD ($) restaurant	Jan. 01, 2019 restaurant
Restructuring and Related Activities [Abstract]
Number of restaurants impaired	8	2	1
Write down related to assets held for sale \| $		$ 3.6
Number of restaurants with write down related to sale		9
Number of restaurants closed	6	5	19
Offset adjustment to closure costs related to lease terminations \| $	$ 0.6	$ 0.4

Amount, before tax, of (gain) loss recognized for the (reversal of write-down) write-down to fair value, less cost to sell, of a disposal group. Excludes discontinued operations.

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