Debt (Schedule Of Outstanding Debt Amount) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013		Dec. 31, 2012
Debt Instrument [Line Items]
Balance outstanding	$ 87.6		$ 43.5
Balance outstanding	992.4		853.0
Balance outstanding	350.2		350.3
Restricted cash and cash equivalents pledged as collateral	116.2		92.4
Revolving Secured Line Of Credit [Member]
Debt Instrument [Line Items]
Balance outstanding	87.6		43.5
Amount available for borrowing	147.4	[1]	191.5	[1]
Interest rate	2.05%		2.08%
Warehouse Facility II [Member]
Debt Instrument [Line Items]
Balance outstanding	162.6		81.3
Amount available for borrowing	162.4	[1]	243.7	[1]
Loans pledged as collateral	230.4		105.2
Restricted cash and cash equivalents pledged as collateral	4.2		3.0
Interest rate	2.18%		2.22%
Warehouse Facility III [Member]
Debt Instrument [Line Items]
Balance outstanding	33.1
Amount available for borrowing	41.9	[1]	75.0	[1]
Loans pledged as collateral	77.4
Restricted cash and cash equivalents pledged as collateral	1.5		0.4
Interest rate	1.81%		1.82%
Warehouse Facility IV [Member]
Debt Instrument [Line Items]
Balance outstanding			37.6
Amount available for borrowing	75.0	[1]	37.4	[1]
Loans pledged as collateral			47.7
Restricted cash and cash equivalents pledged as collateral	0.2		2.5
Interest rate	2.43%		2.96%
Term ABS 2010-1 [Member]
Debt Instrument [Line Items]
Balance outstanding	2.6		80.3
Loans pledged as collateral	69.6		111.6
Restricted cash and cash equivalents pledged as collateral	10.6		12.5
Interest rate	3.63%		2.44%
Term ABS 2011-1 [Member]
Debt Instrument [Line Items]
Balance outstanding	200.5		200.5
Loans pledged as collateral	241.9		243.8
Restricted cash and cash equivalents pledged as collateral	26.4		23.5
Interest rate	2.90%		2.90%
Term ABS 2012-1 [Member]
Debt Instrument [Line Items]
Balance outstanding	201.3		201.3
Loans pledged as collateral	242.2		244.7
Restricted cash and cash equivalents pledged as collateral	26.1		22.3
Interest rate	2.38%		2.38%
Term ABS 2012-2 [Member]
Debt Instrument [Line Items]
Balance outstanding	252.0		252.0
Loans pledged as collateral	304.1		311.9
Restricted cash and cash equivalents pledged as collateral	29.8		26.0
Interest rate	1.63%		1.63%
Term ABS 2013-1 [Member]
Debt Instrument [Line Items]
Balance outstanding	140.3
Loans pledged as collateral	185.6
Restricted cash and cash equivalents pledged as collateral	16.2
Interest rate	1.31%
Senior Notes [Member]
Debt Instrument [Line Items]
Balance outstanding	350.2	[2]	350.3	[2]
Interest rate	9.13%		9.13%
Unamortized debt premium net	$ 0.2		$ 0.3

[1] Availability may be limited by the amount of assets pledged as collateral.

[2] As of September 30, 2013 and December 31, 2012, the outstanding balance presented for the Senior Notes includes a net unamortized debt premium of $0.2 million and $0.3 million, respectively.