Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Jan. 27, 2019	Jan. 28, 2018
Non-current deferred tax asset:
Inventory reserve	$ 4,984	$ 2,406
Bad debt reserve	17	659
Accrued service fees	0	306
Foreign tax credits	2,996	9,987
Research credit carryforward	6,693	11,707
NOL carryforward	8,773	8,326
Payroll and related accruals	8,133	7,344
Share-based compensation	14,150	9,282
Foreign pension deferred	832	477
Accrued sales reserves	763	0
Other deferred assets	1,031	1,847
Valuation allowance	(18,912)	(41,050)
Total non-current deferred tax asset	29,460	11,291
Non-current deferred tax liabilities:
Goodwill and other intangibles	(3,227)	(5,844)
Property, plant and equipment	(6,482)	(4,955)
Repatriation of foreign earnings	(8,158)	(10,427)
Other non-current deferred tax liabilities	(592)	(511)
Total non-current deferred tax liabilities	(18,459)	(21,737)
Net deferred tax assets (liabilities)	$ 11,001
Net deferred tax assets (liabilities)		$ (10,446)