Unaudited Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Oct. 01, 2017	Jan. 01, 2017
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts receivable, current	$ 53	$ 42
Accumulated amortization on other assets	$ 1,551	$ 1,420
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	24,922,998	24,784,367
Common stock, shares outstanding	21,474,173	22,012,651
Treasury stock, shares	3,448,825	2,771,716