CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Jul. 01, 2017	Dec. 31, 2016
CONDENSED CONSOLIDATED BALANCE SHEETS
Accounts receivable, allowance for doubtful accounts (in dollars)	$ 160	$ 160
Property and equipment, net of accumulated depreciation	$ 53,960	$ 53,116
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	50,000	50,000
Common stock, shares issued	20,154	20,040
Common stock, shares outstanding	20,154	20,040
Treasury stock, shares	368	368