Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Jan. 31, 2021	Jan. 26, 2020	Jan. 27, 2019
Net sales	$ 595,117	$ 547,512	$ 627,196
Cost of sales	231,568	210,828	250,174
Gross profit	363,549	336,684	377,022
Operating costs and expenses:
Selling, general and administrative	162,832	163,106	145,246
Product development and engineering	117,529	107,368	109,047
Intangible amortization	8,265	16,546	26,649
Changes in the fair value of contingent earn-out obligations	(33)	(2,345)	(9,419)
Total operating costs and expenses	288,593	284,675	271,523
Operating income	74,956	52,009	105,499
Interest expense	(5,336)	(9,106)	(9,202)
Non-operating income, net	124	2,893	3,823
Investment impairments and credit loss reserves	(6,769)	(1,211)	(30,000)
Income before taxes and equity in net gains (losses) of equity method investments	62,975	44,585	70,120
Provision for income taxes	3,437	12,828	355
Net income before equity in net gains (losses) of equity method investments	59,538	31,757	69,765
Equity in net gains (losses) of equity method investments	329	109	(126)
Net income	59,867	31,866	69,639
Net loss attributable to noncontrolling interest	(36)	(5)	0
Net income attributable to common stockholders	$ 59,903	$ 31,871	$ 69,639
Earnings per share:
Basic (in dollars per share)	$ 0.92	$ 0.48	$ 1.06
Diluted (in dollars per share)	$ 0.91	$ 0.47	$ 1.02
Weighted average number of shares used in computing earnings per share:
Basic (in shares)	65,208	66,263	65,982
Diluted (in shares)	66,059	67,418	68,481