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Summary of Significant Accounting Policies (Schedule of Allowance for Doubtful Receivables) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance at beginning of year	$ 5.3	$ 5.7	$ 4.8
Provision charged (credited) to expense	0	0.4	0.6
Balances written off, net of recoveries	(0.1)	(0.8)	(0.1)
Reclassifications	0.1	0	0.4
Balance at end of year	$ 5.3	$ 5.3	$ 5.7

X

- Definition

Allowance for Doubtful Receivables, Reclassifications

+ References

No definition available.

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- Definition

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Amount of direct write-downs of accounts receivable charged against the allowance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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- Definition

Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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