Leases - Supplemental Balance Sheet Information (Details) - USD ($) $ in Thousands	Oct. 25, 2020	Jan. 26, 2020
Leases [Abstract]
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:OtherAssetsNoncurrent	us-gaap:OtherAssetsNoncurrent
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccruedLiabilitiesCurrent	us-gaap:AccruedLiabilitiesCurrent
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilitiesNoncurrent	us-gaap:OtherLiabilitiesNoncurrent
Operating lease right-of-use assets in "Other assets"	$ 12,159	$ 10,958
Operating lease liabilities in "Accrued liabilities"	3,643	3,273
Operating lease liabilities in "Other long-term liabilities"	9,114	8,185
Total operating lease liabilities	$ 12,757	$ 11,458