Schedule III - Supplemental Insurance Information Schedule III - Supplemental Insurance Information (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Supplementary Insurance Information [Abstract]
Other policy claims and benefits payable	$ 55.3	$ 58.1	$ 51.5
Deferred acquisition costs	819.0	464.0	341.0
Future policy benefits, losses, claims and loss expenses	4,097.0	3,656.0	3,557.0
Net investment income	59.8	56.6	58.8
Benefits, claims, losses and settlement expenses	918.3	824.5	715.5
Amortization of deferred acquisition costs	(625.5)	(852.7)	(531.8)
Other operating expenses	20.0	(41.7)	(45.3)
Supplementary Insurance Information, Other Operating Expense	$ 125.0	$ 115.0	$ 111.0

No definition available.

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- Definition

Amount of amortization of deferred policy acquisition costs recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 235

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-16)

-URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574960-122915

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- Definition

Amount of insurance benefits, claims, losses and settlement expenses incurred.

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- Definition

Net amount of deferred policy acquisition costs capitalized on contracts remaining in force on the balance sheet date.

+ References

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- Definition

Amount of reserves for future policy claims payable and loss expenses to be incurred.

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- Definition

Amount of net investment income earned.

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Amount of other operating expense incurred.

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- Definition

Amount of claims and benefits payable not included within other categories.

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- Definition

Amount of premium revenue earned.

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