Consolidated Statements of Comprehensive (Loss) Income - USD ($)	3 Months Ended		6 Months Ended
	Jun. 16, 2020	Jun. 18, 2019	Jun. 16, 2020	Jun. 18, 2019
Revenue:
Total revenue	$ 104,570,000	$ 121,460,000	$ 214,380,000	$ 235,657,000
Restaurant operating expenses:
Labor and related expenses	31,609,000	36,338,000	66,545,000	72,238,000
Occupancy and other operating expenses	22,389,000	23,703,000	46,797,000	48,136,000
General and administrative	9,432,000	10,849,000	19,298,000	21,314,000
Franchise advertising expenses	2,783,000	3,459,000	5,994,000	6,590,000
Depreciation and amortization	6,285,000	5,813,000	12,422,000	11,720,000
Occupancy and other - franchise subleases and other	1,727,000	993,000	3,322,000	1,847,000
Pre-opening costs	63,000	155,000	296,000	255,000
Impairment of goodwill	0	0	87,277,000	0
Impairment of trademarks	0	0	11,900,000	0
Impairment of long-lived assets	0	3,694,000	8,287,000	3,694,000
Restaurant closure charges, net	499,000	490,000	993,000	1,130,000
Loss on disposal of assets and adjustments to assets held for sale, net	435,000	594,000	557,000	884,000
Total operating expenses	100,864,000	116,943,000	317,625,000	227,481,000
Income (loss) from operations	3,706,000	4,517,000	(103,245,000)	8,176,000
Other expense (income), net
Interest expense	1,281,000	1,722,000	2,789,000	3,506,000
Other income	0	(97,000)	0	(201,000)
Total other expense, net	1,281,000	1,625,000	2,789,000	3,305,000
Income (loss) from operations before provision (benefit) for income taxes	2,425,000	2,892,000	(106,034,000)	4,871,000
Provision (benefit) for income taxes	3,001,000	800,000	(2,990,000)	1,354,000
Net (loss) income	(576,000)	2,092,000	(103,044,000)	3,517,000
Other comprehensive income (loss):
Change in fair value of interest rate cap, net of tax	0	(131,000)	0	(270,000)
Reclassification of interest rate cap amortization included in net income, net of tax	7,000	26,000	52,000	47,000
Total other comprehensive income (loss), net	7,000	(105,000)	52,000	(223,000)
Comprehensive (loss) income	$ (569,000)	$ 1,987,000	$ (102,992,000)	$ 3,294,000
(Loss) earnings per share:
Basic (in dollars per share)	$ (0.02)	$ 0.06	$ (2.78)	$ 0.10
Diluted (in dollars per share)	$ (0.02)	$ 0.06	$ (2.78)	$ 0.09
Weighted-average shares outstanding
Basic (in shares)	37,086,962	36,821,728	37,081,511	36,988,853
Diluted (in shares)	37,086,962	37,083,799	37,081,511	37,215,059
Company restaurant sales
Revenue:
Revenue	$ 95,261,000	$ 112,180,000	$ 195,594,000	$ 218,083,000
Franchise revenue
Revenue:
Revenue	4,520,000	4,638,000	8,911,000	8,703,000
Franchise advertising contributions
Revenue:
Revenue	2,783,000	3,459,000	5,994,000	6,590,000
Franchise sublease and other income
Revenue:
Revenue	2,006,000	1,183,000	3,881,000	2,281,000
Food and paper costs
Restaurant operating expenses:
Cost, Direct Material	$ 25,642,000	$ 30,855,000	$ 53,937,000	$ 59,673,000