Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2017	Sep. 27, 2016	Oct. 03, 2017	Sep. 27, 2016
Revenue:
Restaurant revenue	$ 113,020	$ 121,442	$ 340,175	$ 354,511
Franchising royalties and fees	1,191	1,239	3,543	3,563
Total revenue	114,211	122,681	343,718	358,074
Restaurant operating costs (exclusive of depreciation and amortization shown separately below):
Cost of sales	29,955	33,112	91,640	95,465
Labor	36,897	40,973	112,921	117,723
Occupancy	12,709	13,792	39,340	40,794
Other restaurant operating costs	15,811	18,470	49,152	53,958
General and administrative	9,807	15,251	29,866	35,128
Depreciation and amortization	6,183	7,006	18,729	20,983
Pre-opening	69	856	860	2,689
Restaurant impairments, closure costs and asset disposals	10,263	2,283	35,147	14,547
Total costs and expenses	121,694	131,743	377,655	381,287
Loss from operations	(7,483)	(9,062)	(33,937)	(23,213)
Interest expense, net	893	738	2,828	1,964
Loss before income taxes	(8,376)	(9,800)	(36,765)	(25,177)
(Benefit) provision for income taxes	(41)	41	230	1,124
Net loss	(8,335)	(9,841)	(36,995)	(26,301)
Accretion of preferred stock to redemption value	0	0	(7,967)	0
Net loss attributable to common stockholders	$ (8,335)	$ (9,841)	$ (44,962)	$ (26,301)
Loss per share of Class A and Class B common stock, combined:
Basic (USD per share)	$ (0.20)	$ (0.35)	$ (1.23)	$ (0.95)
Diluted (USD per share)	$ (0.20)	$ (0.35)	$ (1.23)	$ (0.95)
Weighted average shares of Class A and Class B common stock outstanding, combined:
Basic (in shares)	41,109,827	27,802,020	36,639,382	27,786,827
Diluted (in shares)	41,109,827	27,802,020	36,639,382	27,786,827