System Optimization (Gains) Losses, Net Summary of DavCo and NPC Transactions (Details) $ in Thousands		3 Months Ended	12 Months Ended
	May 31, 2017 USD ($) number_of_restaurants	Jul. 02, 2017 USD ($)	Dec. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jan. 01, 2017 USD ($)
Property, Plant and Equipment
Goodwill			$ 747,884	$ 743,334	$ 741,410
Proceeds from sales			3,223	81,516	262,173
System optimization gains (losses), net		$ (41,050)	463	(39,076)	71,931
DavCo Acquisition
Property, Plant and Equipment
Restaurants acquired from franchisees | number_of_restaurants	140
Restaurants closed before acquisition | number_of_restaurants	7
Total consideration paid	$ 86,788			86,788
Net assets held for sale				70,688
Capital lease assets				49,360
Deferred taxes				27,830
Capital lease obligations				(97,797)
Net unfavorable leases				(22,330)
Other liabilities				(6,924)
Total identifiable net assets				20,827
Goodwill				65,961
Favorable Lease Assets				1,229
Unfavorable Lease Liabilities				23,559
Supplemental deferred purchase price				6,269
Tax deductible goodwill				21,795
NPC Disposition
Property, Plant and Equipment
Number of sold restaurants to be reimaged | number_of_restaurants	90
Number of restaurants to be built by the end of 2022 | number_of_restaurants	15
Proceeds from sales	$ 70,688			70,688
Net assets sold				(70,688)
Goodwill				(65,961)
Net favorable leases				24,034
Other				(1,708)
System optimization gains (losses), net			$ 0	(43,635)	$ 0
Favorable Lease Assets				30,068
Unfavorable Lease Liabilities				$ 6,034