Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

The number of grants made 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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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

Price of a single share of a number of saleable stocks of a company.

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No definition available.

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Gross number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
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STOCK BASED COMPENSATION - Restricted Stock Units (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2017	Apr. 30, 2016	Jul. 26, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 7.0	$ 2.0	$ 11.0	$ 3.0
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU's granted (in shares)			1,028,534
Stock-based compensation expense	$ 4.0	$ 0.0	$ 5.3	$ 0.0
IPO \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price (in USD per share)					$ 24.79
Management \| IPO \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU's granted (in shares)			1,366,383
Director \| IPO \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU's granted (in shares)			41,635
Ordinary Shares \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share price (in USD per share)	$ 27.15		$ 27.15
Shares issued during period (in shares)			70,700
Treasury shares acquired, at cost (in shares)			(8,528)
Stock-based compensation expense	$ 3.0		$ 4.3
Compensation costs not yet recognized	$ 29.5		$ 29.5