Computation of Basic and Diluted Net Income Per Common Share - Reconciliation of Numerator and Denominator of Basic and Diluted Net Income Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 30, 2017	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2016	Oct. 01, 2016	Jul. 02, 2016	Apr. 02, 2016	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Numerator:
Net (loss) income	$ (5,155)	$ (3,096)	$ (2,750)	$ (1,866)	$ (10,815)	$ (671)	$ (328)	$ 101	$ (12,867)	$ (11,713)	$ 474
Denominator:
Weighted average shares of common stock (basic)									11,555	10,173	9,962
Effect of dilutive stock options											154
Effect of dilutive contingent shares											12
Weighted average shares of common stock (diluted)									11,555	10,173	10,128
Per share data:
Basic net (loss) income per share	$ (0.44)	$ (0.27)	$ (0.24)	$ (0.16)	$ (1.04)	$ (0.07)	$ (0.03)	$ 0.01	$ (1.11)	$ (1.15)	$ 0.05
Diluted net (loss) income per share	$ (0.44)	$ (0.27)	$ (0.24)	$ (0.16)	$ (1.04)	$ (0.07)	$ (0.03)	$ 0.01	$ (1.11)	$ (1.15)	$ 0.05