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		6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Numerator:
Net loss	$ (2,419)	$ (3,280)	$ (5,467)	$ (6,883)
Denominator:
Weighted average shares of common stock (basic)	13,648	11,644	13,639	11,636
Weighted average shares of common stock (diluted)	13,648	11,644	13,639	11,636
Per share data:
Basic net loss per share	$ (0.18)	$ (0.28)	$ (0.40)	$ (0.59)
Diluted net loss per share	$ (0.18)	$ (0.28)	$ (0.40)	$ (0.59)