Fair Value Measurements (Details) (USD $)											3 Months Ended
	Mar. 31, 2012 Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member]	Mar. 31, 2012 Fair Value, Measurements, Recurring [Member] Estimate of Fair Value, Fair Value Disclosure [Member]	Dec. 31, 2011 Fair Value, Measurements, Recurring [Member] Estimate of Fair Value, Fair Value Disclosure [Member]	Mar. 31, 2012 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 1 [Member]	Dec. 31, 2011 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 1 [Member]	Mar. 31, 2012 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 2 [Member]	Dec. 31, 2011 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 2 [Member]	Mar. 31, 2012 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2011 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 3 [Member]	Mar. 31, 2012 Notes Payable, Other Payables [Member] Minimum [Member]	Mar. 31, 2012 Notes Payable, Other Payables [Member] Maximum [Member]	Mar. 31, 2012 Line of Credit Facility - Unsecured [Member] Minimum [Member]	Mar. 31, 2012 Notes Receivable [Member] Minimum [Member]	Mar. 31, 2012 Notes Receivable [Member] Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Discount Rate											3.50%	4.90%	4.10%	7.33%	8.19%
Notes Receivable, Fair Value	$ 23,400,000	$ 35,300,000
Trading Securities, Fair Value Disclosure			23,411,000	21,713,000	23,411,000	21,713,000	0	0	0	0
Notes Payable, Fair Value	1,900,000,000	2,100,000,000
Total			23,411,000	21,713,000	23,411,000	21,713,000	0	0	0	0
Derivative Liabilities			$ (59,000)	$ (37,000)		$ 0	$ (60,000)	$ (38,000)	$ 1,000	$ 1,000