Summary of Significant Accounting Policies - Weighted Average Number of Shares Outstanding Used to Compute Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 02, 2016	Jul. 04, 2015	Jul. 02, 2016	Jul. 04, 2015
Accounting Policies [Abstract]
Net income (loss)	$ 3,861	$ 1,782	$ 17,411	$ (191)
Weighted-average number of common shares outstanding
Basic weighted-average common shares outstanding (in shares)	11,155	11,062	11,127	11,012
Dilutive potential common shares (in shares)	109	214	118	0
Diluted weighted-average common shares outstanding (in shares)	11,264	11,276	11,245	11,012
Earnings (loss) per share
Basic (in dollars per share)	$ 0.35	$ 0.16	$ 1.56	$ (0.02)
Diluted (in dollars per share)	$ 0.34	$ 0.16	$ 1.55	$ (0.02)