Basis of Presentation and Summary of Significant Accounting Policies - Adjustments for Topic 842 (Details) - USD ($) $ in Thousands	Mar. 26, 2019	Jan. 02, 2019	Jan. 01, 2019	Mar. 27, 2018	Jan. 02, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash and cash equivalents	$ 9,024	$ 7,153	$ 7,153	$ 10,038	$ 6,559
Accounts and other receivables, net	3,215	3,167	3,167
Inventories	2,673	2,932	2,932
Prepaid expenses and other current assets	2,487	2,371	4,935
Assets held for sale	2,747	14,794	14,794
Total current assets	20,146	30,417	32,981
Property and equipment, net	149,549	147,590	161,429
Operating lease right-of-use assets	223,542	218,855	0
Goodwill	324,120	321,531	321,531
Trademarks	220,300	220,300	220,300
Intangible assets, net	11,691	10,931	18,507
Other assets, net	4,158	4,208	4,208
Total assets	953,506	953,832	758,956
Accounts payable	19,014	19,877	19,877
Other accrued liabilities	32,901	34,360	34,785
Current portion of finance lease obligations, other debt and deemed landlord financing liabilities	481	486	1,033
Current portion of operating lease liabilities	20,146	17,303	0
Total current liabilities	72,542	72,026	55,695
Long-term debt, finance lease obligations, other debt and deemed landlord financing liabilities, excluding current portion, net	154,573	159,624	178,664
Operating lease liabilities, excluding current portion	217,967	213,313	0
Deferred income taxes	70,332	70,179	69,471
Other non-current liabilities	15,396	14,504	32,852
Total liabilities	530,810	529,646	336,682
Commitments and contingencies
Preferred stock, $0.0001 par value; 1,000,000 shares authorized; no shares issued and outstanding	0	0	0
Common stock, $0.0001 par value; 400,000,000 shares authorized; 37,049,140 shares issued and outstanding at March 26, 2019; 37,305,342 shares issued and outstanding at January 1, 2019	4	4	4
Additional paid-in capital	334,144	336,941	336,941
Accumulated other comprehensive income	62	180	180
Retained earnings	88,486	87,061	85,149
Total shareholders’ equity	422,696	424,186	422,274	$ 420,239	$ 416,249
Total liabilities and shareholders’ equity	$ 953,506	953,832	$ 758,956
Topic 842
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash and cash equivalents		0
Accounts and other receivables, net		0
Inventories		0
Prepaid expenses and other current assets		(2,564)
Assets held for sale		0
Total current assets		(2,564)
Property and equipment, net		(13,839)
Operating lease right-of-use assets		218,855
Goodwill		0
Trademarks		0
Intangible assets, net		(7,576)
Other assets, net		0
Total assets		194,876
Accounts payable		0
Other accrued liabilities		(425)
Current portion of finance lease obligations, other debt and deemed landlord financing liabilities		(547)
Current portion of operating lease liabilities		17,303
Total current liabilities		16,331
Long-term debt, finance lease obligations, other debt and deemed landlord financing liabilities, excluding current portion, net		(19,040)
Operating lease liabilities, excluding current portion		213,313
Deferred income taxes		708
Other non-current liabilities		(18,348)
Total liabilities		192,964
Commitments and contingencies
Preferred stock, $0.0001 par value; 1,000,000 shares authorized; no shares issued and outstanding		0
Common stock, $0.0001 par value; 400,000,000 shares authorized; 37,049,140 shares issued and outstanding at March 26, 2019; 37,305,342 shares issued and outstanding at January 1, 2019		0
Additional paid-in capital		0
Accumulated other comprehensive income		0
Retained earnings		1,912
Total shareholders’ equity		1,912
Total liabilities and shareholders’ equity		$ 194,876