Selected Quarterly Financial and Earnings Data (Unaudited) (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Jan. 01, 2017 USD ($)	Oct. 02, 2016 USD ($)	Jul. 03, 2016 USD ($)	Apr. 03, 2016 USD ($)	Jan. 03, 2016 USD ($)	Sep. 27, 2015 USD ($)	Jun. 28, 2015 USD ($)	Mar. 29, 2015 USD ($)	Jan. 01, 2017 USD ($)	Jan. 03, 2016 USD ($)	Dec. 28, 2014 USD ($)	Dec. 30, 2012
Effect of Fourth Quarter Events [Line Items]
Restaurants Acquired	27	11	6	12	46	5	4		56	55	123	278
Acquisition-related costs	$ 800	$ 500	$ 200	$ 400	$ 800	$ 100		$ 200
Impairment and other lease charges	1,200	$ 700	300	$ 200	$ 300	$ 400	$ 700	$ 1,600	$ 2,355	$ 3,078	$ 3,541
Insured Event, Gain (Loss)	$ 700		$ 500						$ (1,200)
Number of Restaurants	753	734	723	717	705	660	657	659	753	705
Gain (Loss) on Condemnation				$ 500
Income tax expense, valuation allowance	$ (30,400)								$ (30,374)	$ 2,959	$ 24,326
Closed restaurants	9
Weeks In fiscal period					14				52	53	52
Damage from Fire, Explosion or Other Hazard [Member]
Effect of Fourth Quarter Events [Line Items]
Properties damaged in fire	1		1						2
Unfavorable Regulatory Action [Member]
Effect of Fourth Quarter Events [Line Items]
Number of Restaurants	1			1					1