Computation of Basic and Diluted Earnings per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 01, 2021	Oct. 02, 2020	Oct. 01, 2021	Oct. 02, 2020
Numerators:
Consolidated net income	$ 13,603	$ 8,258	$ 36,577	$ 31,865
Denominators:
Weighted average common shares outstanding—basic	35,447	35,142	35,366	35,144
Dilutive potential common shares	317	546	405	465
Weighted average common shares outstanding— diluted	35,764	35,688	35,771	35,609
Antidilutive potential common shares excluded from above	1		18	17
Earnings per Common Share:
Basic	$ 0.38	$ 0.23	$ 1.03	$ 0.91
Diluted	$ 0.38	$ 0.23	$ 1.02	$ 0.89