Business Combinations (Details) shares in Millions			3 Months Ended	12 Months Ended
	Feb. 01, 2016 USD ($)	Aug. 03, 2015 USD ($) shares	Oct. 31, 2015 USD ($) shares	Oct. 31, 2017 USD ($)	Oct. 31, 2016 USD ($)	Oct. 31, 2015 USD ($)	Oct. 31, 2014 USD ($)
Business Acquisition [Line Items]
Outstanding				$ 392,972,000	$ 486,303,000
Acquisition and integration costs				0	4,613,000	$ 25,539,000
Goodwill				267,458,000	266,974,000
Software and Software-Related Services
Business Acquisition [Line Items]
Goodwill				$ 201,428,000	$ 201,428,000
8.0% Cyan Convertible Senior Notes due 2019
Business Acquisition [Line Items]
Interest rate on convertible notes			8.00%			8.00%
Cyan, Inc
Business Acquisition [Line Items]
Consideration transferred, equity interests, conversion ratio, equity component		0.19936
Consideration transferred, equity interests, conversion ratio, cash component		0.63
Acquisition of business, net of cash acquired		$ 33,621,000
Outstanding principal of debt assumed in acquisition		48,836,000
Acquisition and integration costs						$ 25,500,000
Non-cash share-based compensation expense						7,600,000
Increase in inventory valuation		3,100,000
Goodwill		256,434,000
Revenue of Cyan since acquisition			$ 84,400,000
Business Acquisition, Pro Forma Information [Abstract]
Pro forma revenue						2,565,081,000
Pro forma net income						16,286,000
Cyan, Inc | Acquisition-related Costs
Business Acquisition, Pro Forma Information [Abstract]
Acquisition related costs						25,500,000	$ 25,500,000
Cyan, Inc | Fair Value Adjustment to Inventory
Business Acquisition, Pro Forma Information [Abstract]
Acquisition related costs						3,100,000	3,100,000
Cyan, Inc | Warrant and Bifurcation of Convertible Debt Adjustments
Business Acquisition, Pro Forma Information [Abstract]
Acquisition related costs						60,600,000	$ 4,700,000
Cyan, Inc | Networking Platforms
Business Acquisition [Line Items]
Goodwill		55,000,000
Cyan, Inc | Software and Software-Related Services
Business Acquisition [Line Items]
Goodwill		$ 201,400,000
Cyan, Inc | Customer relationships | Minimum
Business Acquisition [Line Items]
Intangible assets, useful life		4 years
Cyan, Inc | Customer relationships | Maximum
Business Acquisition [Line Items]
Intangible assets, useful life		7 years
Cyan, Inc | Developed technology | Minimum
Business Acquisition [Line Items]
Intangible assets, useful life		5 years
Cyan, Inc | Developed technology | Maximum
Business Acquisition [Line Items]
Intangible assets, useful life		7 years
Cyan, Inc | Restricted Stock Units (RSUs)
Business Acquisition [Line Items]
Equity interest issued as consideration (in shares) | shares		1.0
Cyan, Inc | Stock Options
Business Acquisition [Line Items]
Equity interest issued as consideration (in shares) | shares		2.4
Cyan, Inc | Common Stock
Business Acquisition [Line Items]
Equity interest issued as consideration (in shares) | shares		10.6
Cyan, Inc | 8.0% Cyan Convertible Senior Notes due 2019 | Convertible Debt
Business Acquisition [Line Items]
Outstanding principal of debt assumed in acquisition		$ 50,000,000
Interest rate on convertible notes		8.00%
Number of shares converted for each $1000 principal amount			0.09179
Conversion price on common stock per thousand dollars in principal			$ 290.08
Outstanding			$ 0			$ 0
Convertible shares, number of shares converted (in shares) | shares			4.6
Equity component of convertible note acquired			$ 14,500,000
TeraXion Inc.
Business Acquisition [Line Items]
Acquisition of business, net of cash acquired	$ 32,000,000
Goodwill	$ 10,083,000
TeraXion Inc. | Developed technology
Business Acquisition [Line Items]
Intangible assets, useful life	5 years