System Optimization (Losses) Gains, Net Davco and NPC Transactions (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 02, 2017 USD ($) Restaurant	Jul. 03, 2016 USD ($)	Jul. 02, 2017 USD ($)	Jul. 03, 2016 USD ($)	Jan. 01, 2017 USD ($)
Property, Plant and Equipment [Line Items]
Goodwill	$ 742,407		$ 742,407		$ 741,410
Proceeds from sales of restaurants			77,980	$ 45,078
System optimization (losses) gains, net	$ (41,050)	$ 1,924	(39,643)	10,350
NPC Disposition [Member]
Property, Plant and Equipment [Line Items]
Significant Changes, Franchises Sold | Restaurant	140
Proceeds from sales of restaurants	$ 70,688
Net Assets Sold	(70,688)
Goodwill	(65,503)
Net favorable leases	24,034
Other	1,680
Favorable lease assets	30,068
Unfavorable lease liabilities	$ 6,034
Number of sold restaurants to be remodeled by the end of 2021 | Restaurant	90
Number of new restaurants to be built by the end of 2022 | Restaurant	15
DavCo and NPC Transactions [Member]
Property, Plant and Equipment [Line Items]
System optimization (losses) gains, net	$ (43,149)	$ 0	(43,149)	$ 0
DavCo Acquisition [Member]
Property, Plant and Equipment [Line Items]
Restaurants acquired from franchisees | Restaurant	140
Total consideration paid	$ 86,788
Net assets held for sale	70,688		70,688
Capital lease assets	49,360		49,360
Deferred taxes	27,493		27,493
Capital lease obligations	(97,046)		(97,046)
Net unfavorable leases	(22,211)		(22,211)
Other liabilities	(6,999)		(6,999)
Total identifiable net assets	21,285		21,285
Goodwill	65,503		65,503
Favorable lease assets	1,228
Unfavorable lease liabilities	23,439
Supplemental deferred purchase price	6,344
Tax deductible goodwill	$ 21,871		$ 21,871
Number of restaurants closed before acquisition | Restaurant	7