Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 27, 2017	Sep. 28, 2016	Sep. 27, 2017	Sep. 28, 2016	Dec. 28, 2016
Property, Plant and Equipment [Abstract]
Depreciation	$ 4,700	$ 4,100	$ 13,600	$ 11,800
Gross value of assets under capital leases for buildings and improvements	1,600		1,600		$ 1,600
Accumulated depreciation of assets under capital leases	1,500		1,500		$ 1,500
Capital expenditures	9,300	12,100	28,300	26,500
Capital expenditures for restaurant remodeling	100	100	2,900	1,600
Capital expenditures for new restaurants	7,100	10,800	21,000	20,800
Impairment of property and equipment	$ 15,000	$ 2,454	$ 15,480	$ 2,508