Loan Securitization (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2012 Y	Dec. 31, 2011	Mar. 31, 2011
Debt Instrument [Line Items]
Instruments issued by the securitization entity	$ 600,000,000
Class A notes annual interest rate of one-month LIBOR plus	one-month LIBOR plus 1.45%
Loans, unpaid balance due, payable date	Feb. 17, 2014
Expected average term, years	2.93
Net yield rate	0.00%
Incremental interest rate over base rate	1.30%
Company repurchased notes	172,000,000
Total notes amount	428,000,000	600,000,000	600,000,000
Debt defeasance costs	848,000
Class A Notes [Member]
Debt Instrument [Line Items]
Instruments issued by the securitization entity	600,000,000
Incremental interest rate over base rate	1.45%
Balance Before Repurchase [Member]
Debt Instrument [Line Items]
Total notes amount	$ 600,000,000