Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Jan. 29, 2017	Jan. 31, 2016
Components of Deferred Tax Assets and Liabilities [Abstract]
Deferred revenue	$ 6,229	$ 4,295
Inventory reserve	3,096	2,931
Bad debt reserve	645	521
Accrued service fees	0	238
Research and development charges	0	584
Research credit carryforward	25,770	32,605
NOL carryforward	42,870	38,979
Payroll and related accruals	12,556	8,773
Share-based compensation	5,524	5,006
Foreign pension deferred	727	0
Other deferred assets	5,918	6,281
Valuation allowance	(82,961)	(77,383)
Total non-current deferred tax asset	20,374	22,830
Inventory reserve - foreign	0	(515)
Goodwill and other intangibles	(12,534)	(16,895)
Property, plant and equipment	(7,483)	(3,518)
Other non-current deferred tax liabilities	(1,745)	(1,350)
Total non-current deferred tax liabilities	(21,762)	(22,278)
Deferred tax liabilities	$ (1,388)
Deferred tax assets		$ 552