Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Retained Earnings (Accumulated Deficit)
Beginning Balance, Shares at Jan. 02, 2018		38,434,274
Beginning Balance at Jan. 02, 2018	$ 416,249
Net income (loss)	3,229				$ 3,229
Other comprehensive income (loss), net of tax	180			$ 180
Comprehensive income (loss)	3,409
Stock-based compensation	1,274		$ 1,274
Issuance of vested restricted stock, net of shares withheld for tax withholding, shares		9,892
Issuance of vested restricted stock, net of shares withheld for tax withholding	(79)		(79)
Exercise of stock options, shares		4,750
Exercise of stock options	48		48
Repurchase of common stocks and warrants, shares		0
Repurchase of common stocks and warrants	(34)		(34)
Ending Balance, Shares at Mar. 27, 2018		38,448,916
Ending Balance at Mar. 27, 2018	420,160	$ 4	350,543	194	69,419
Beginning Balance, Shares at Jan. 02, 2018		38,434,274
Beginning Balance at Jan. 02, 2018	416,249
Net income (loss)	7,439
Other comprehensive income (loss), net of tax	305
Comprehensive income (loss)	7,744
Issuance of vested restricted stock, net of shares withheld for tax withholding	(79)
Ending Balance, Shares at Jun. 19, 2018		38,091,165
Ending Balance at Jun. 19, 2018	421,172	$ 4	347,220	319	73,629
Beginning Balance, Shares at Mar. 27, 2018		38,448,916
Beginning Balance at Mar. 27, 2018	420,160	$ 4	350,543	194	69,419
Net income (loss)	4,210				4,210
Other comprehensive income (loss), net of tax	125			125
Comprehensive income (loss)	4,335
Stock-based compensation	1,359		1,359
Issuance of vested restricted stock, net of shares withheld for tax withholding, shares		42,570
Exercise of stock options, shares		7,500
Exercise of stock options	75		75
Repurchase of common stocks and warrants, shares		(407,821)
Repurchase of common stocks and warrants	(4,757)		(4,757)
Ending Balance, Shares at Jun. 19, 2018		38,091,165
Ending Balance at Jun. 19, 2018	421,172	$ 4	347,220	319	73,629
Adjustment for adoption of accounting standards, net of tax	1,912				1,912
Beginning Balance, Shares at Jan. 01, 2019		37,305,342
Beginning Balance at Jan. 01, 2019	422,274	$ 4	336,941	180	85,149
Net income (loss)	1,425				1,425
Other comprehensive income (loss), net of tax	(118)			(118)
Comprehensive income (loss)	1,307
Stock-based compensation	1,577		1,577
Issuance of vested restricted stock, net of shares withheld for tax withholding, shares		13,172
Issuance of vested restricted stock, net of shares withheld for tax withholding	(84)		(84)
Exercise of stock options, shares		1,500
Exercise of stock options	16		16
Repurchase of common stocks and warrants, shares		(270,874)
Repurchase of common stocks and warrants	(4,306)		(4,306)
Ending Balance, Shares at Mar. 26, 2019		37,049,140
Ending Balance at Mar. 26, 2019	422,696	$ 4	334,144	62	88,486
Beginning Balance, Shares at Jan. 01, 2019		37,305,342
Beginning Balance at Jan. 01, 2019	422,274	$ 4	336,941	180	85,149
Net income (loss)	3,517
Other comprehensive income (loss), net of tax	(223)
Comprehensive income (loss)	3,294
Issuance of vested restricted stock, net of shares withheld for tax withholding	(84)
Ending Balance, Shares at Jun. 18, 2019		36,795,532
Ending Balance at Jun. 18, 2019	423,308	$ 4	332,769	(43)	90,578
Beginning Balance, Shares at Mar. 26, 2019		37,049,140
Beginning Balance at Mar. 26, 2019	422,696	$ 4	334,144	62	88,486
Net income (loss)	2,092				2,092
Other comprehensive income (loss), net of tax	(105)			(105)
Comprehensive income (loss)	1,987
Stock-based compensation	1,677		1,677
Issuance of vested restricted stock, net of shares withheld for tax withholding, shares		48,499
Exercise of stock options, shares		1,500
Exercise of stock options	15		15
Repurchase of common stocks and warrants, shares		(303,607)
Repurchase of common stocks and warrants	(3,067)		(3,067)
Ending Balance, Shares at Jun. 18, 2019		36,795,532
Ending Balance at Jun. 18, 2019	$ 423,308	$ 4	$ 332,769	$ (43)	$ 90,578