Income Taxes - Reconciliation of the Provision for Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Apr. 26, 2020	Jan. 31, 2021	Jan. 26, 2020	Jan. 27, 2019
Income Tax Disclosure [Abstract]
Federal income tax at statutory rate		$ 13,309	$ 9,328	$ 14,725
State income taxes, net of federal benefit		(186)	68	(55)
Foreign taxes differential, including withholding taxes		(2,688)	(966)	2,910
Tax credits generated		(4,361)	(2,026)	(3,344)
Changes in valuation allowance	$ (15,800)	(438)	(2,722)	(23,029)
Non-taxable gain on sale		0	6,802	0
Changes in uncertain tax positions		1,841	8,636	2,219
Equity compensation		(3,573)	(6,008)	786
Revaluation of deferred tax assets and liabilities		270	538	1,164
Impact of US Tax Reform		0	0	1,904
Other		(737)	(822)	3,075
Provision for income taxes		3,437	$ 12,828	$ 355
Increase to general business credits		5,000
Reduction to foreign tax credits		$ 6,900

Effective Income Tax Rate Reconciliation, Nontaxable Gain on Sale

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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