Derivative Financial Instruments - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended																	9 Months Ended				9 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Sep. 30, 2013	Jun. 30, 2014 Futures contracts [Member] Contract	Sep. 30, 2013 Futures contracts [Member] Contract	Jun. 30, 2014 Nomura Fund Linked Note [Member]	Jun. 16, 2014 Nomura Fund Linked Note [Member]	Jun. 30, 2014 Call options [Member]	Sep. 30, 2013 Call options [Member]	Jun. 30, 2014 Swap [Member] Natural Gas Commodity Contract [Member] MMBTU	Sep. 30, 2013 Swap [Member] Natural Gas Commodity Contract [Member] MMBTU	Jun. 30, 2014 Swap [Member] Oil Commodity Contract [Member] MBbls	Sep. 30, 2013 Swap [Member] Oil Commodity Contract [Member] MBbls	Jun. 30, 2014 Spectrum Brands [Member]	Sep. 30, 2013 Spectrum Brands [Member]	Jun. 30, 2014 Spectrum Brands [Member] Standby Letters of Credit [Member]	Sep. 30, 2013 Spectrum Brands [Member] Standby Letters of Credit [Member]	Jun. 30, 2014 Spectrum Brands [Member] Zinc Commodity Swap Contract [Member] T	Jun. 30, 2014 Spectrum Brands [Member] Silver Commodity Swap Contract [Member] ozt	Sep. 30, 2013 Spectrum Brands [Member] Silver Commodity Swap Contract [Member] ozt	Jun. 30, 2014 Spectrum Brands [Member] Bronze Commodity Contract [Member]	Jun. 30, 2014 Spectrum Brands [Member] Interest Rate Contract [Member]	Jun. 30, 2014 Spectrum Brands [Member] Foreign exchange contracts [Member]	Jun. 30, 2014 Remainder of 2014 [Member] Swap [Member] Natural Gas Commodity Contract [Member] MMBTU	Jun. 30, 2014 Remainder of 2014 [Member] Swap [Member] Oil Commodity Contract [Member] MBbls	Jun. 30, 2014 Year Two [Member] Swap [Member] Natural Gas Commodity Contract [Member]	Jun. 30, 2014 Year Two [Member] Swap [Member] Oil Commodity Contract [Member] MBbls	Jun. 30, 2014 Not Designated as Hedging Instrument [Member]	Sep. 30, 2013 Not Designated as Hedging Instrument [Member]	Jun. 30, 2014 Cash and Cash Equivalents [Member] Call options [Member]	Sep. 30, 2013 Cash and Cash Equivalents [Member] Call options [Member]	Jun. 30, 2014 Derivatives For Trading And Investment [Member] Not Designated as Hedging Instrument [Member] Futures contracts [Member]	Sep. 30, 2013 Derivatives For Trading And Investment [Member] Not Designated as Hedging Instrument [Member] Futures contracts [Member]	Jun. 30, 2014 Derivatives For Trading And Investment [Member] Not Designated as Hedging Instrument [Member] Commodity contracts [Member]	Jun. 30, 2014 Derivatives For Trading And Investment [Member] Not Designated as Hedging Instrument [Member] Call options [Member]	Sep. 30, 2013 Derivatives For Trading And Investment [Member] Not Designated as Hedging Instrument [Member] Call options [Member]
Derivative Financial Instruments [Line Items]
Derivative, Fixed Interest Rate																								1.36%
Derivative Asset, Collateral, Obligation to Return Cash, Offset										$ 209,300,000	$ 72,000,000																					$ 152,100,000	$ 72,000,000
Derivative, Average Forward Price																										103.82	4.47	97.62
Natural Gas, Volume												8,211,000.0	16,018,000													8,211,000.0
Derivative Asset, Fair Value, Gross Asset										324,600,000	221,800,000																			338,600,000	227,700,000			100,000	0	100,000	324,600,000	221,800,000
Contract value																				9,900,000	700,000	1,000,000	3,900,000		221,500,000
Derivative, Nonmonetary Notional Amount																					35	45
Derivative net loss/gain																				0				0	2,100,000
Derivative net loss/gain, net of tax benefit/expense																				0					600,000
Derivative net loss/gain, non-controlling interest																								0	1,500,000
Estimated amount of derivative net losses/gains to be reclassified from AOCI into earnings over the next twelve months	(1,300,000)	600,000	(2,200,000)	100,000																0				0	2,000,000
Derivative, Notional Amount	7,163,300,000		7,163,300,000		6,407,400,000											154,300,000	108,500,000							300,000,000
Weight of raw materials under derivative contract																				5
Cash collateral						8,700,000	5,900,000									500,000
Standby letters of credit																		0	0
Call options purchased to match the funding requirements			Call options are one, two and three year options
FGL purchases call options to fund the next index credit			One, two or three year call options to fund the next index credit
Futures contracts						2,016	1,693
Derivative, Percentage of Production Volume Covered by Derivative Financial Instruments	68.00%	77.00%	74.00%	70.00%
Derivative, Commodity Contract, Oil Volume														323,000.0	375.0												137,000.0		186,000.0
Derivative Asset, Fair Value, Amount Offset Against Collateral										115,300,000	149,800,000
Investment Owned, Balance, Principal Amount									35,000,000
Embedded Derivative, Fair Value of Embedded Derivative Liability								$ 11,600,000	$ 11,300,000