Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 26, 2019	Jun. 27, 2018	Jun. 26, 2019	Jun. 27, 2018
Revenue
Total revenue	$ 113,740	$ 111,633	$ 222,717	$ 217,389
Cost of operations
Food and paper cost	27,886	28,681	55,038	55,916
Labor and related expenses	29,272	27,856	58,848	55,518
Occupancy and other operating expenses	23,032	22,913	46,259	44,832
Company restaurant expenses	80,190	79,450	160,145	156,266
General and administrative expenses	9,348	12,474	20,696	25,676
Franchise expenses	7,542	6,250	13,686	12,082
Depreciation and amortization	4,454	4,344	9,215	8,556
Loss (gain) on disposal of assets	134	(8)	178	53
Recovery of securities lawsuits related legal expenses	(10,000)	(2,429)	(10,000)	(4,063)
Asset impairment and closed-store reserves	565	3,963	874	6,782
Gain (Loss) on Disposition of Business	927	0	5,051	0
Total expenses	93,160	104,044	199,845	205,352
Income from operations	20,580	7,589	22,872	12,037
Interest expense, net	922	960	1,781	1,848
Income tax receivable agreement (income) expense	(94)	712	77	(206)
Income before provision for income taxes	19,752	5,917	21,014	10,395
Provision for income taxes	5,665	865	6,014	2,814
Net income	$ 14,087	$ 5,052	$ 15,000	$ 7,581
Net income per share
Basic (usd per share)	$ 0.37	$ 0.13	$ 0.39	$ 0.20
Diluted (usd per share)	$ 0.37	$ 0.13	$ 0.38	$ 0.19
Weighted-average shares used in computing net income per share
Basic (shares)	37,939,912	38,482,074	38,296,807	38,473,641
Diluted (shares)	38,580,722	39,043,434	39,043,477	39,015,259
Company-operated restaurant revenue
Revenue
Total revenue	$ 100,139	$ 99,627	$ 197,289	$ 194,180
Franchise revenue
Revenue
Total revenue	7,918	6,553	14,362	12,659
Franchise advertising fee revenue
Revenue
Total revenue	$ 5,683	$ 5,453	$ 11,066	$ 10,550