Commitments and Contingencies - Additional Information (Detail) (USD $)	9 Months Ended			9 Months Ended						9 Months Ended			1 Months Ended	9 Months Ended
	Jun. 30, 2014	Nov. 01, 2013	Apr. 06, 2011	Jun. 30, 2014 Maximum [Member]	Jun. 30, 2014 Minimum [Member]	Jun. 30, 2014 FGLH [Member]	Apr. 06, 2011 FGLH [Member]	Jun. 30, 2014 Spectrum Brands [Member]	Jun. 30, 2014 OMGUK CARVM financing fee [Member]	Jun. 30, 2014 Cressy Plaintiff [Member]	Jun. 30, 2014 Unasserted Claim [Member] Maximum [Member]	Jun. 30, 2014 Unasserted Claim [Member] Minimum [Member]	Jul. 31, 2012 Unasserted Claim [Member] FGLH [Member]	Jun. 30, 2014 Unasserted Claim [Member] FGLH [Member]
Commitment And Contingencies [Line Items]
Loss Contingency, Receivable										$ 4,500,000
Reserves for legal, environmental and regulatory matters	24,900,000								6,100,000
Business Acquisition Fair Value Of Contingent Purchase Price Consideration Reduction							50,000,000
Environmental costs recognized, capitalized								4,700,000
Document Period End Date	Jun. 30, 2014
Accrued amount of guaranty fund assessments						4,400,000
Estimated future premium tax deductions						4,700,000
Pre-tax charge, net of reinsurance, to increase reserves to cover potential benefits payable													11,000,000
Administrative costs and potential liabilities														2,000,000
Estimated range of external legal costs											3,000,000	1,000,000
Loss Contingency Accrual, Payments														0.4
Notional amount of unfunded, legally binding lending commitments	164,600,000
Expiration of partial amount of unfunded, legally binding lending commitments	37,000,000
Expiry date of partial amount of notional amount				1 year
Expiry date of remainder part of notional amount				5 years	1 year
Statutory Accounting Practices, Change in Statutory Capital and Surplus Required as a Result of Electing New Statutory Accounting Practice		11,500,000
Statutory Accounting Practices, Statutory Capital and Surplus, Unassigned Balance Netted Against Additional Paid in Capital			805,800,000
Litigation Settlement, Amount										5,300,000
Loss Contingency Accrual, Provision										9,900,000
Estimated Litigation Liability										$ 7,300,000