Significant Accounting Policies - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2021	Jan. 26, 2020	Jan. 27, 2019
Accounting Policies [Abstract]
Aggregate net investments under cost method of accounting	$ 24,100	$ 19,400
Total equity method investments	3,100	3,300
Investment impairments and credit loss reserves	$ (6,769)	(1,211)	$ (30,000)
Percent of realizable undiscounted cash flows used to determine useful life of acquired finite-lived intangible assets, minimum	90.00%
Advertising costs	$ 1,000	900	600
Recoveries from nonrecurring engineering services	$ 9,600	$ 8,400	$ 4,400