Business Segment Information - Reconciliation of Consolidated Net Income (Loss) to Adjusted EBITDA (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 02, 2022	Jan. 03, 2021	Dec. 29, 2019
Segment Reporting Information [Line Items]
Net income (loss)	$ 10,370	$ (10,211)	$ (84,386)
Loss (income) from discontinued operations, net of tax	(18,455)	6,825	82,391
Provision for (benefit from) income taxes	1,083	(7,044)	11,830
Income (loss) before income taxes	(7,002)	(10,430)	9,835
Non-general and administrative adjustments:
Depreciation and amortization	20,600	22,000	22,200
Impairment and other lease charges	1,670	9,139	13,101
Goodwill impairment	0	0	67,909
Loss on extinguishment of debt	5,307	1,241	0
Continuing Operations
Segment Reporting Information [Line Items]
Net income (loss)	10,370	(10,211)	(84,386)
Loss (income) from discontinued operations, net of tax	(18,455)	(6,825)	(82,391)
Provision for (benefit from) income taxes	1,083	(7,044)	11,830
Income (loss) before income taxes	(7,002)	(10,430)	9,835
Non-general and administrative adjustments:
Depreciation and amortization	20,574	22,009	22,186
Impairment and other lease charges	1,538	8,023	15
Interest expense	374	292	325
Closed restaurant rent expense, net of sublease income	2,999	4,331	3,260
Other expense (income), net	478	(2,098)	862
Stock-based compensation expense	4,200	2,800	2,400
Total non-general and administrative adjustments	26,016	32,630	26,718
General and administrative adjustments:
Stock-based compensation expense	4,200	2,800	2,400
Restructuring costs and retention bonuses	18	686	891
Digital and brand repositioning costs	1,821	424	207
Transaction costs	0
Total general and administrative adjustments	6,002	3,791	3,418
Adjusted EBITDA	25,016	25,991	39,971
Restaurant Wages And Related Expenses | Continuing Operations
Non-general and administrative adjustments:
Stock-based compensation expense	53	73	70
General and administrative adjustments:
Stock-based compensation expense	53	73	70
General and Administrative Expense | Continuing Operations
Non-general and administrative adjustments:
Stock-based compensation expense	4,163	2,681	2,320
General and administrative adjustments:
Stock-based compensation expense	4,163	2,681	2,320
Pollo Tropical
Non-general and administrative adjustments:
Goodwill impairment	0	0	0
Operating Segments
Non-general and administrative adjustments:
Impairment and other lease charges	1,538	8,023	15
Operating Segments | Pollo Tropical | Continuing Operations
Segment Reporting Information [Line Items]
Income (loss) before income taxes	5,261	2,557	20,300
Non-general and administrative adjustments:
Depreciation and amortization	19,962	21,112	21,476
Impairment and other lease charges	1,570	8,023	15
Interest expense	2,532	2,405	1,953
Closed restaurant rent expense, net of sublease income	1,946	2,093	3,260
Other expense (income), net	362	(2,373)	862
Total non-general and administrative adjustments	26,425	31,333	27,636
General and administrative adjustments:
Restructuring costs and retention bonuses	78	551	827
Digital and brand repositioning costs	1,821	424	207
Transaction costs	677
Total general and administrative adjustments	5,116	2,627	2,624
Adjusted EBITDA	36,802	36,517	50,560
Operating Segments | Pollo Tropical | Restaurant Wages And Related Expenses | Continuing Operations
Non-general and administrative adjustments:
Stock-based compensation expense	53	73	70
General and administrative adjustments:
Stock-based compensation expense	53	73	70
Operating Segments | Pollo Tropical | General and Administrative Expense | Continuing Operations
Non-general and administrative adjustments:
Stock-based compensation expense	2,540	1,652	1,590
General and administrative adjustments:
Stock-based compensation expense	2,540	1,652	1,590
Other | Continuing Operations
Segment Reporting Information [Line Items]
Income (loss) before income taxes	(12,263)	(12,987)	(10,465)
Non-general and administrative adjustments:
Depreciation and amortization	612	897	710
Impairment and other lease charges	(32)	0	0
Interest expense	(2,158)	(2,113)	(1,628)
Closed restaurant rent expense, net of sublease income	1,053	2,238	0
Other expense (income), net	116	275	0
Total non-general and administrative adjustments	(409)	1,297	(918)
General and administrative adjustments:
Restructuring costs and retention bonuses	(60)	135	64
Digital and brand repositioning costs	0	0	0
Transaction costs	(677)
Total general and administrative adjustments	886	1,164	794
Adjusted EBITDA	(11,786)	(10,526)	(10,589)
Other | Restaurant Wages And Related Expenses | Continuing Operations
Non-general and administrative adjustments:
Stock-based compensation expense	0	0	0
General and administrative adjustments:
Stock-based compensation expense	0	0	0
Other | General and Administrative Expense | Continuing Operations
Non-general and administrative adjustments:
Stock-based compensation expense	1,623	1,029	730
General and administrative adjustments:
Stock-based compensation expense	$ 1,623	$ 1,029	$ 730