Goodwill and Other Intangible assets and Liabilities - Additional Information (Detail)		12 Months Ended
	Sep. 24, 2014 USD ($) Restaurants	Dec. 30, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 25, 2013 USD ($)
Schedule Of Intangible Assets And Goodwill [Line Items]
Proceeds from sale of restaurant	$ 5,400,000
Restaurant disposition, decrease in goodwill	650,000	$ 0	$ 650,000
Gain on disposition of restaurant	$ 2,700,000		2,658,000	$ 400,000
Number of restaurants | Restaurants	6
Impairment losses to goodwill		0
Amortization expense		$ 156,000	$ 227,000	$ 213,000
Favorable Leasehold Interest [Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Intangible asset subject to amortization, weighted average amortization period		4 years
Unfavorable Leasehold Interest [Member]
Schedule Of Intangible Assets And Goodwill [Line Items]
Intangible asset subject to amortization, weighted average amortization period		9 years