Computation of Basic and Diluted Net Loss Per Common Share - Reconciliation of Numerator and Denominator of Basic and Diluted Net Loss Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Apr. 01, 2017
Numerator:
Net (loss) income	$ (3,603)	$ (1,866)
Denominator:
Weighted average shares of common stock (basic)	11,628	11,518
Weighted average shares of common stock (diluted)	11,628	11,518
Per share data:
Basic net (loss) income per share	$ (0.31)	$ (0.16)
Diluted net (loss) income per share	$ (0.31)	$ (0.16)