Restaurant Impairment, Closure Costs and Asset Disposals - Narrative (Details) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 01, 2019 restaurant	Oct. 02, 2018 USD ($) restaurant	Oct. 01, 2019 restaurant	Oct. 02, 2018 USD ($) restaurant
Property, Plant and Equipment Impairment or Disposal [Abstract]
Number of restaurants impaired during the comparable periods	0	0	2	1
Closure costs | $		$ 1.5		$ 3.6
Number of restaurants closed		3		12