Earnings per Share - Schedule of Basic and Diluted Net Income per Share Data (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 18, 2019	Mar. 26, 2019	Jun. 19, 2018	Mar. 27, 2018	Jun. 18, 2019	Jun. 19, 2018
Numerator:
Net income	$ 2,092	$ 1,425	$ 4,210	$ 3,229	$ 3,517	$ 7,439
Denominator:
Weighted-average shares outstanding - basic (in shares)	36,821,728		38,299,483		36,988,853	38,370,595
Weighted-average shares outstanding - diluted	37,083,799		38,643,873		37,215,059	38,938,106
Net (loss) income per share - basic (in dollars per share)	$ 0.06		$ 0.11		$ 0.10	$ 0.19
Net (loss) income per share - diluted (in dollars per share)	$ 0.06		$ 0.11		$ 0.09	$ 0.19
Antidilutive stock options, unvested restricted stock awards, unvested RSUs and warrants excluded from the computations (in dollars per share)	5,865,601		143,226		6,205,932	125,577
Restricted Stock and RSUs [Member]
Denominator:
Dilutive effect (in shares)	254,317		321,331		221,626	318,329
Stock Options [Member]
Denominator:
Dilutive effect (in shares)	7,754		5,875		4,580	13,427
Warrants [Member]
Denominator:
Dilutive effect (in shares)	0		17,184		0	235,755