Segment Reporting - Sales Information by Product (Detail) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended		9 Months Ended
	Jan. 27, 2018	Oct. 28, 2017	Jan. 28, 2017	Oct. 29, 2016	Oct. 28, 2017	Oct. 29, 2016	Jan. 27, 2018	Jan. 28, 2017
Segment Reporting Information [Line Items]
Net sales	$ 1,375,222	$ 1,375,222	$ 1,397,418	$ 1,397,418	$ 4,065,074	$ 4,148,095	$ 4,065,074	$ 4,148,095
Consumable
Segment Reporting Information [Line Items]
Net sales		1,074,189		1,064,098	3,270,385	3,252,551
Equipment and software
Segment Reporting Information [Line Items]
Net sales		222,574		249,047	540,860	627,187
Other
Segment Reporting Information [Line Items]
Net sales		$ 78,459		$ 84,273	$ 253,829	$ 268,357