Segment Information - Net Sales Activity by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 25, 2020	Oct. 27, 2019	Oct. 25, 2020	Oct. 27, 2019
Revenue from External Customer [Line Items]
Net sales	$ 154,082	$ 141,011	$ 430,444	$ 409,511
Semiconductor Products Group
Revenue from External Customer [Line Items]
Net sales	$ 154,082	$ 141,011	$ 430,444	$ 409,511