Consolidated Securitization Vehicles (Details 16) (Securitization Vehicles, USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012		Dec. 31, 2011
Fair Value	$ (19,089)		$ (24,942)
Interest Rate Swaps
Notional Amount	273,711
Fair Value	(19,089)		(24,942)
Interest Rate	5.01%
Derivative Maturity	Dec. 31, 2015
Interest Rate Swaps | SwissRe
Notional Amount	223,802
Fair Value	(15,631)		(20,540)
Interest Rate	5.10%	[1]
Derivative Counterparty	Swiss RE Financial
Derivative Maturity	Dec. 31, 2015
Interest Rate Swaps | Bank of America
Notional Amount	34,270
Fair Value	(1,499)		(2,368)
Interest Rate	4.58%	[1]
Derivative Counterparty	Bank of America
Derivative Maturity	Dec. 31, 2014
Interest Rate Swaps | BankOfAmerica1Member
Notional Amount	10,535
Fair Value	(1,387)		(1,461)
Interest Rate	5.05%	[1]
Derivative Counterparty	Bank of America
Derivative Maturity	Dec. 31, 2016
Interest Rate Swaps | BankOfAmerica2Member
Notional Amount	5,104
Fair Value	$ (572)		$ (573)
Interest Rate	4.12%	[1]
Derivative Counterparty	Bank of America
Derivative Maturity	Dec. 31, 2016

[1] Represents the gross fixed interest rate we pay to our counterparties under these derivative instruments. We receive an amount of interest indexed to one-month LIBOR on all of our interest rate swaps.