Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Dec. 29, 2017	Dec. 30, 2016
Accounts receivable, net of allowance for contract losses and doubtful accounts	$ 3,526	$ 3,417
Preferred Stock, Par or Stated Value Per Share	$ 0.001	$ 0.001
Preferred Stock, Shares Authorized	2,000	2,000
Preferred Stock, Shares Outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	80,000	80,000
Common stock, shares issued	32,853	32,853
Treasury stock, shares	7,084	7,256