Reverse Mortgage Related Assets - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended			3 Months Ended		1 Months Ended
	Sep. 30, 2014	Mar. 31, 2014	Sep. 30, 2014	Sep. 30, 2014 Maximum [Member]	Sep. 30, 2014 Minimum [Member]	Sep. 30, 2014 Zero Collateral Value [Member]	Sep. 30, 2014 Collateral Value Reduced by One Percent [Member]	Jul. 31, 2011 SASCO 2002-RM1's Class O Securities [Member] Mortgage-Backed Securities ("MBS") [Member]
Reverse Mortgage Loan Activities [Line Items]
Trading securities, par value	$ 0		$ 0					$ 2,500,000
Investments purchase percentage								100.00%
Income tax benefit		6,700,000
Consolidated mortgage investment	29,400,000		29,400,000
Average age of a mortgage backed securities borrower			92 years
Realizable collateral value of mortgage backed securities	51,100,000		51,100,000
Forecasted housing prices increase rate			2.50%
Forecasted housing prices increase rate, following year and thereafter			2.00%
Internal rate of return			16.34%			14.83%	15.65%
Cash payments to reverse mortgagors	7,100,000		7,100,000
Decrease in income	230,000					502,000
Reduction in collateral value	1.00%
Net present value increase or decrease				$ 384,000	$ 381,000
Change in present value of IRR				1.00%	1.00%