Acquisitions and Divestitures Acquisitions (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended			3 Months Ended
	Nov. 01, 2014		Oct. 26, 2013	Nov. 01, 2014	Jan. 26, 2013
Business Acquisition
Finite-Lived Intangible Asset, Useful Life	4 years 1 month 6 days	[1]	0 years 6 months 29 days
Vistapointe
Business Acquisition
Effective Date of Acquisition	Sep. 11, 2014
Total purchase price				$ 16.9
Cash consideration				16.9
Acquisition Cost Expensed				0.4
Finite-Lived Intangible Asset, Useful Life	5 years
Vyatta
Business Acquisition
Effective Date of Acquisition	Nov. 09, 2012
Total purchase price					44.8
Cash consideration					43.6
Prepaid license fees consideration					1.2
Consideration Paid Held In Escrow, Amount					7.0
Consideration Paid Held In Escrow, Escrow Duration					18 months
Acquisition Cost Expensed					$ 0.4

[1] During the fiscal year ended November 1, 2014, $477.3 million of finite-lived intangible assets became fully amortized and, therefore, were removed from the balance sheet.