Significant Accounting Policies - Changes in Accumulated Other Comprehensive Income (Loss) by Component (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 26, 2020	Jan. 27, 2019	Jan. 28, 2018
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ 682,580	$ 665,351	$ 605,263
Other comprehensive income (loss)	(2,559)	(2,407)	94
Ending balance	677,200	682,580	665,351
Accumulated Other Comprehensive Loss
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(3,607)	(1,200)	(1,294)
Ending balance	(6,166)	(3,607)	(1,200)
Defined Benefit Plans
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(4,511)	(2,030)	(2,414)
Other comprehensive income (loss)	(4,991)	(2,481)	384
Ending balance	(9,502)	(4,511)	(2,030)
Foreign Currency Hedge
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	74	0	290
Other comprehensive income (loss)	(74)	74	(290)
Ending balance	0	74	0
Available-for-Sale Securities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	0	0	0
Other comprehensive income (loss)	2,506	0	0
Ending balance	2,506	0	0
Cumulative Translation Adjustment
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	830	830	830
Other comprehensive income (loss)	0	0	0
Ending balance	$ 830	$ 830	$ 830