Net Income Per Common Share - Calculation of EPS and Reconciliation of Weighted Average Common Shares Used in Calculation of Basic and Diluted EPS (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Oct. 03, 2020	Sep. 28, 2019
Earnings Per Share [Abstract]
Net income	$ 17,322	$ 15,106	$ 35,121	$ 40,408
Weighted-average common shares - Basic	58,963	58,433	58,858	58,320
Add: Dilutive shares from equity plans	479	709	433	872
Weighted-average common shares - Diluted	59,442	59,142	59,291	59,192
Net income per common share:
Basic	$ 0.29	$ 0.26	$ 0.60	$ 0.69
Diluted	$ 0.29	$ 0.26	$ 0.59	$ 0.68