Significant Accounting Policies - Changes in Accumulated Other Comprehensive Income (Loss) by Component (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 27, 2019	Jan. 28, 2018	Jan. 29, 2017
Defined benefit plan
Beginning balance	$ (2,030)	$ (2,414)	$ 0
Other comprehensive income (loss)	(2,481)	384	(2,414)
Ending balance	(4,511)	(2,030)	(2,414)
Other
Beginning balance	830	830	701
Other comprehensive income	0	0	129
Ending balance	830	830	830
Accumulated Other Comprehensive Income (Loss)
Beginning balance	(1,200)	(1,294)	653
Other comprehensive income (loss)	(2,407)	94	(1,947)
Ending balance	(3,607)	(1,200)	(1,294)
Foreign currency cash flow hedges
Derivatives
Beginning balance	0	290	0
Other comprehensive income (loss)	74	(290)	290
Ending balance	74	0	290
Interest rate cap
Derivatives
Beginning balance	0	0	(48)
Other comprehensive income (loss)	0	0	48
Ending balance	$ 0	$ 0	$ 0