Sale of Quality Assurance and Information Technology Infrastructure Businesses (Details) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended				12 Months Ended
	Oct. 26, 2017	Mar. 31, 2017	Oct. 29, 2017	Jul. 30, 2017	Apr. 30, 2017	Jan. 29, 2017	Oct. 28, 2018	Oct. 29, 2017	Oct. 27, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain from divestitures			$ (48,033)	$ 0	$ (3,938)	$ 0	$ 0	$ (51,971)
Net proceeds from divestitures							$ 0	81,102
Quality Assurance Business | Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Purchase price									$ 66,400
Gain from divestitures								$ (48,000)
Income before provision for income taxes	$ 4,500
Quality Assurance Business | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Post-closing support services agreement, period (up to)		6 months
Maintech Holdings, LLC | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net proceeds from divestitures		$ 18,300
Working capital adjustment		$ 100
Working capital adjustment determination period		60 days
Proceeds, net of fees, expenses, and repayment outstanding loan		$ 13,100
Gain on disposal		$ 3,900
Post-closing support services agreement, period (up to)		6 months
Helpdesk and network monitoring services, service agreement, period		3 years