Segment Information - Revenue by Geographic Region (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Jan. 27, 2019	Oct. 28, 2018	Jul. 29, 2018	Apr. 29, 2018	Jan. 28, 2018	Oct. 29, 2017	Jul. 30, 2017	Apr. 30, 2017	Jan. 27, 2019	Jan. 28, 2018	Jan. 29, 2017
Geographic Information And Concentration Of Risk [Line Items]
Net sales	$ 160,006	$ 173,550	$ 163,211	$ 130,429	$ 140,614	$ 150,304	$ 153,127	$ 143,802	$ 627,196	$ 587,847	$ 544,272
Asia-Pacific
Geographic Information And Concentration Of Risk [Line Items]
Net sales									480,680	439,342	412,167
North America
Geographic Information And Concentration Of Risk [Line Items]
Net sales									118,664	121,144	94,123
Europe
Geographic Information And Concentration Of Risk [Line Items]
Net sales									49,353	43,580	43,378
Other: Warrant Shares
Geographic Information And Concentration Of Risk [Line Items]
Net sales offset									$ (21,501)	$ (16,219)	$ (5,396)
Net sales revenue
Geographic Information And Concentration Of Risk [Line Items]
Concentration risk, percentage									100.00%	100.00%	100.00%
Net sales revenue | Asia-Pacific
Geographic Information And Concentration Of Risk [Line Items]
Concentration risk, percentage									76.00%	75.00%	76.00%
Net sales revenue | North America
Geographic Information And Concentration Of Risk [Line Items]
Concentration risk, percentage									19.00%	21.00%	17.00%
Net sales revenue | Europe
Geographic Information And Concentration Of Risk [Line Items]
Concentration risk, percentage									8.00%	7.00%	8.00%
Net sales revenue | Other: Warrant Shares
Geographic Information And Concentration Of Risk [Line Items]
Allocated share-based compensation expense as a percentage of net revenue									(3.00%)	(3.00%)	(1.00%)