SHARE-BASED COMPENSATION EXPENSE (Details Textual) $ / shares in Units, $ in Millions	6 Months Ended
Apr. 30, 2016 USD ($) period $ / shares shares	Apr. 30, 2015 USD ($) $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period, net, acquisitions	2,400,000
Unrecognized share-based compensation \| $	$ 85.1
2008 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance under plan (in shares)	25,100,000
Remaining authorized shares available for issuance (in shares)	3,900,000
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units granted in period, net, acquisition	1,000,000
Total fair value of restricted stock units vested and converted into common stock \| $	$ 33.0	$ 23.0
Weighted average fair value of each restricted stock unit granted (per share) \| $ / shares	$ 19.73	$ 18.68
Unrecognized share-based compensation \| $	$ 83.9
Weighted-average period for recognition of share-based compensation (in years)	1 year 6 months
Restricted Stock Units (RSUs) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of service-based awards	3 years
Restricted Stock Units (RSUs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of service-based awards	4 years
Employee Stock Options and Stock Appreciation Rights \| 2008 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum expiration period of incentive awards	10 years
Minimum exercise price, percentage of fair market value on grant date	100.00%
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of service-based awards	4 years
Intrinsic value of option exercised \| $	$ 2.5	$ 0.8
Unrecognized share-based compensation \| $	$ 1.2
Weighted-average period for recognition of share-based compensation (in years)	1 year 4 months 13 days
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)	6,500,000
Offer period for ESPP	12 months
Number of purchase periods in offer period \| period	2
Length of purchase period	6 months
ESPP discount percentage purchase date	85.00%
Maximum number of shares increase under ESPP (in shares)	600,000
Shares issued under ESPP (in shares)	500,000
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

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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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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