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
-Section S99
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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

+ References

No definition available.

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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

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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).

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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-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

Percentage of vesting of share-based compensation awards.

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- Definition

Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Employee Benefit Plans - Performance-Based Restricted Stock Units (Details) - Performance Shares [Member] - USD ($) $ / shares in Units, $ in Millions	1 Months Ended				12 Months Ended
	Nov. 16, 2016	Nov. 30, 2015	Nov. 30, 2014	Nov. 30, 2013	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense					$ 12.5	$ 8.6	$ 2.6
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of percentage of units vested upon achieving performance criteria					0.00%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of percentage of units vested upon achieving performance criteria					200.00%
November Two Thousand Thirteen Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target number of performance units				350,000
Number of units earned					406,250
Liabilities for share-based compensation					$ 12.3
Grant date fair value per unit				$ 19.64
Share-based compensation expense					4.4	5.2	2.6
November Two Thousand Fourteen Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target number of performance units			290,000
Grant date fair value per unit			$ 23.62
Share-based compensation expense					4.1	3.4	0.0
November Two Thousand Fifteen Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Target number of performance units		330,000
Grant date fair value per unit		$ 30.81
Share-based compensation expense					$ 4.0	$ 0.0	$ 0.0
Subsequent Event [Member] \| November Two Thousand Thirteen Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awarded	406,250