SHARE-BASED COMPENSATION EXPENSE (Details Textual) $ / shares in Units, $ in Millions	9 Months Ended
Jul. 31, 2017 USD ($) period $ / shares shares	Jul. 31, 2016 USD ($) $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation \| $	$ 76.5
2017 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum expiration period of incentive awards (in years)	10 years
Shares authorized for issuance under plan (in shares)	8,900,000.0
Remaining authorized shares available for issuance (in shares)	10,400,000
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 (in years) \| $	$ 41.5	$ 41.3
Weighted average fair value of each restricted stock unit granted (in dollars per share) \| $ / shares	$ 23.36	$ 19.72
Unrecognized share-based compensation \| $	$ 76.3
Weighted-average period for recognition of share-based compensation (in years)	1 year 5 months 12 days
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
Restricted stock units (RSUs) \| 2017 Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of service-based awards (in years)	1 year
Employee Stock Options and Stock Appreciation Rights \| 2017 Plan
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%
Employee Stock \| 2003 Employee Stock Purchase Plan
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
Length of purchase period (in years)	6 months
ESPP discount percentage purchase date (as a percent)	85.00%
Maximum number of shares increase under ESPP (in shares)	600,000
Shares issued under ESPP (in shares)	1,000,000
Employee Stock \| 2003 Employee Stock Purchase Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance under plan (in shares)	8,200,000
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	$ 4.6
Unrecognized share-based compensation \| $	$ 0.2
Weighted-average period for recognition of share-based compensation (in years)	1 year 22 days

Maximum Number of Annual Shares Increase under ESPP

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

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Unrecognized cost of unvested share-based compensation awards.

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-Name Accounting Standards Codification
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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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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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Discount rate from fair value on purchase date that participants pay for shares.

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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).

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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.

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

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