Goodwill and Intangibles, including DAC and VOBA, net - Summary of Definite Lived Intangible Assets (Detail) (USD $) In Millions, unless otherwise specified			12 Months Ended			12 Months Ended			12 Months Ended			12 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 Minimum	Sep. 30, 2013 Maximum	Sep. 30, 2013 Customer relationships	Sep. 30, 2012 Customer relationships	Sep. 30, 2013 Customer relationships Minimum	Sep. 30, 2013 Customer relationships Maximum	Sep. 30, 2013 Trade names	Sep. 30, 2012 Trade names	Sep. 30, 2013 Trade names Minimum	Sep. 30, 2013 Trade names Maximum	Sep. 30, 2013 Technology assets	Sep. 30, 2012 Technology assets	Sep. 30, 2013 Technology assets Minimum	Sep. 30, 2013 Technology assets Maximum
Finite-Lived Intangible Assets [Line Items]
Cost	$ 1,229.6	$ 1,038.0			$ 885.9	$ 796.2			$ 171.6	$ 150.8			$ 172.1	$ 91.0
Accumulated Amortization	(244.5)	(164.1)			(160.8)	(113.0)			(44.7)	(28.3)			(39.0)	(22.8)
Net	$ 985.1	$ 873.9			$ 725.1	$ 683.2			$ 126.9	$ 122.5			$ 133.1	$ 68.2
Amortizable Life			1 year	20 years			15 years	20 years			1 year	12 years			4 years	17 years

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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