Acquisitions (Details)	3 Months Ended	12 Months Ended
	Dec. 28, 2014 USD ($) Restaurant	Jan. 03, 2016 USD ($) Restaurant	Dec. 28, 2014 USD ($) Restaurant	Dec. 29, 2013 USD ($) Restaurant
Business Acquisition [Line Items]
Goodwill	$ 822,562,000	$ 770,781,000	$ 822,562,000	$ 842,544,000
Series of Individually Immaterial Business Acquisitions [Member]
Business Acquisition [Line Items]
Restaurants acquired from franchisees | Restaurant		4	27	1
Total consideration paid, net of cash received		$ 1,232,000	$ 27,630,000
Goodwill	11,455,000	(1,408,000)	11,455,000
Properties	9,498,000	1,303,000	9,498,000
Acquired franchise rights	6,650,000	760,000	6,650,000
Other assets	941,000	0	941,000
Capital lease obligations	0	(438,000)	0
Unfavorable leases	0	(440,000)	0
Other liabilities	(565,000)	(80,000)	(565,000)
Total identifiable net assets	16,524,000	1,105,000	16,524,000
Business Combination, Consideration Transferred, Net of Identifiable Assets Acquired and Liabilities Assumes	11,106,000	127,000	11,106,000
Gain on acquisition of restaurants		$ 0	349,000
Prior period acquisition [Member] | Series of Individually Immaterial Business Acquisitions [Member]
Business Acquisition [Line Items]
Restaurants acquired from franchisees | Restaurant		3
Goodwill	$ 0	$ (1,535,000)	0
Sale of franchise-operated restaurant to franchisee [Member] | Series of Individually Immaterial Business Acquisitions [Member]
Business Acquisition [Line Items]
Restaurants acquired from franchisees | Restaurant	18
Total consideration paid, net of cash received	$ 26,324,000
Goodwill	0		0
Properties	10,359,000		10,359,000
Acquired franchise rights	$ 0		$ 0