Stock-based Compensation Plans (Narrative) (Details) $ / shares in Units, $ in Millions	3 Months Ended
Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($)
Allocated Share-based Compensation Expense \| $	$ 2.4	$ 3.6
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized \| $	$ 6.7
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	1,042,254
Phantom Share Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Intrinsic Value, Amount Per Share \| $ / shares	$ 8.60
Share-based compensation liability \| $	$ 1.3
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	542,212
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	233,471
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Share-based compensation, units awarded but not yet granted	235,876
Minimum [Member] \| Performance Shares [Member]
Performance Factor	0
Maximum [Member] \| Performance Shares [Member]
Performance Factor	2
Share-based Compensation Award, Tranche One [Member] \| Performance Shares [Member]
Performance Factor	2
Share-based Compensation Award, Tranche Two [Member] \| Performance Shares [Member]
Performance Factor	2
Share-based Compensation Award, Tranche Three [Member] \| Performance Shares [Member]
Performance Factor	0

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- Definition

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

+ References

No definition available.

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- Definition

Performance-based restricted stock units awarded by the Company for which performance criteria have not yet been set and related to future performance periods.

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Antidilution
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=6510752

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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- Definition

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

Unrecognized cost of unvested share-based compensation awards.

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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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- Definition

Per share weighted average intrinsic value of equity-based compensation awards not vested. Excludes stock and unit options.

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- Definition

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

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