Increase decrease in fair value of equity conversion feature of preferred stock.

No definition available.

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5618551-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (a),(c),(d),(e)

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

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Derivative Financial Instruments - Summary of Gain (Loss) Recognized in Income on Derivatives (Detail) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Jun. 30, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Derivative Instruments, Gain (Loss) [Line Items]
Increase Decrease In Fair Value Of Equity Conversion Feature Of Preferred Stock			$ 12.7	$ 101.6
Embedded Derivative, Gain (Loss) on Embedded Derivative, Net	$ (1.0)	$ (1.0)	(0.1)	0.0
Equity conversion feature of preferred stock \| Gain from the change in the fair value of the equity conversion feature of preferred stock
Derivative Instruments, Gain (Loss) [Line Items]
Gain Recognized in Income on Derivatives			12.7	(101.6)
Commodity contracts \| Other (expense) income, net
Derivative Instruments, Gain (Loss) [Line Items]
Gain Recognized in Income on Derivatives		(25.3)	6.6	(1.3)
Bronze Commodity Contract [Member] \| Consumer products cost of goods sold
Derivative Instruments, Gain (Loss) [Line Items]
Gain Recognized in Income on Derivatives		0.1	0.1	(0.1)
Foreign exchange contracts \| Other (expense) income, net
Derivative Instruments, Gain (Loss) [Line Items]
Gain Recognized in Income on Derivatives		2.5	(3.1)	(3.6)
Call options \| Net investment gains
Derivative Instruments, Gain (Loss) [Line Items]
Gain Recognized in Income on Derivatives		106.3	(246.0)	(151.6)
Futures contracts \| Net investment gains
Derivative Instruments, Gain (Loss) [Line Items]
Gain Recognized in Income on Derivatives		7.0	(25.5)	(17.5)
FIA embedded derivatives \| Benefits and other changes in policy reserves
Derivative Instruments, Gain (Loss) [Line Items]
Gain Recognized in Income on Derivatives		$ (241.3)	$ (363.7)	$ (6.4)