Schedule III - Supplemental Insurance Information Schedule III - Supplemental Insurance Information (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Supplementary Insurance Information [Abstract]
Future policy benefits, losses, claims and loss expenses	$ 1,751.3	$ 1,856.0	$ 1,418.4
Benefits, claims, losses and settlement expenses	63.5	68.2	61.7
Amortization of deferred acquisition costs	(103.0)	(70.6)	(66.9)
Supplementary Insurance Information, Other Operating Expense	$ 9.6	$ 13.4	$ 11.4

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- Definition

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

+ 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

+ Details

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- Definition

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

+ References

+ Details

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- Definition

Amount of net investment income earned.

+ References

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- Definition

Amount of other operating expense incurred.

+ References

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