Consolidated Statements Of Income And Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 27, 2016	Dec. 29, 2015	Dec. 30, 2014
Consolidated Statements Of Income And Comprehensive Income [Abstract]
Revenues	$ 351,681	$ 331,612	$ 301,805
Costs and expenses:
Costs of sales	99,181	95,963	90,990
Restaurant operating expenses	169,300	156,337	137,695
Marketing and advertising costs	8,260	7,745	6,169
Pre-opening costs	3,446	5,228	4,735
General and administrative costs	25,924	23,111	20,537
Lease termination and closing costs	1,031	1,386
Secondary public offering costs			5
Impairment charges	598	3,248	3,536
Depreciation and amortization	18,865	16,776	13,598
Operating income	25,076	21,818	24,540
Other income (expense), net:
Interest, net of capitalized interest	(70)	(77)	(113)
Other	(432)	(236)	(107)
Income before income taxes	24,574	21,505	24,320
Income tax expense	6,808	5,507	7,723
Net income	$ 17,766	$ 15,998	$ 16,597
Basic earnings per common share	$ 0.76	$ 0.68	$ 0.71
Diluted earnings per common share	$ 0.76	$ 0.68	$ 0.70
Shares used in computing earnings (loss) per common share:
Basic	23,322,344	23,380,085	23,517,883
Diluted	23,435,275	23,517,288	23,740,318
Comprehensive income	$ 17,766	$ 15,998	$ 16,597