Maximum Number of Annual Shares Increase under ESPP

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- Definition

Number of Purchase Periods in Offer Period

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Purchase Period

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No definition available.

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- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Exercise Price Minimum, Percentage Of Fair Market Value On Grant Date

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Expiration Period Maximum

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Offer Period

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No definition available.

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- Definition

Share-based Compensation Arrangement Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value, Acquisitions

+ References

No definition available.

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- Definition

Share-based Compensation Arrangements By Share-based Payment Award, Options, Grants In Period, Weighted Average Exercise Price, Acquisitions, Acquired Company's Awards

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Subparagraph (a)(1)
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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Net number of share options (or share units) granted during the period.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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Share-Based Compensation Expense (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Oct. 31, 2017 USD ($) period $ / shares shares	Oct. 31, 2016 USD ($) $ / shares shares	Oct. 31, 2015 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted during the period (in shares)	0	0	0
Weighted average fair values of stock options granted in exchange for Cyan awards (dollars per share) \| $ / shares			$ 13.04
Unrecognized share-based compensation \| $	$ 69.9
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of service-based awards (in years)	4 years
Intrinsic value of option exercised \| $	$ 3.1	$ 5.7	$ 11.8
Unrecognized share-based compensation \| $	$ 0.1
Nonvested award compensation cost not yet recognized, period for recognition	10 months 24 days
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of restricted stock units vested and converted into common stock \| $	$ 49.5	$ 50.3	$ 50.5
Weighted average fair value of each restricted stock unit granted (per share) \| $ / shares	$ 23.29	$ 19.81	$ 19.41
Weighted average fair value of restricted stock units granted in exchange for Cyan awards (per share) \| $ / shares	$ 25.39
Unrecognized share-based compensation \| $	$ 69.8
Nonvested award compensation cost not yet recognized, period for recognition	1 year 5 months
Restricted Stock Units (RSUs) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of service-based awards (in years)	3 years
Restricted Stock Units (RSUs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of service-based awards (in years)	4 years
2017 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum expiration period of incentive awards (in years)	10 years
Number of shares authorized (in shares)	8,900,000.0
Remaining authorized shares available for issuance (in shares)	10,200,000
2017 Omnibus Incentive Plan \| Employee Stock Options and Stock Appreciation Rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum expiration period of incentive awards (in years)	10 years
Minimum exercise price, percentage of fair market value on grant date (as a percent)	100.00%
2017 Omnibus Incentive Plan \| Restricted Stock Units (RSUs) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of service-based awards (in years)	1 year
2003 Employee Stock Purchase Plan \| Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining authorized shares available for issuance (in shares)	5,500,000
Offer period for ESPP (in years)	12 months
Number of purchase periods in offer period \| period	2
Purchase period	6 months
ESPP discount percentage purchase date	85.00%
Maximum number of shares increase under ESPP	600,000
Shares issued under ESPP	1,000,000	1,100,000	1,000,000
2003 Employee Stock Purchase Plan \| Employee Stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	8,200,000