Debt (Summary Of Additional Information Of Credit facilities) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Revolving Secured Line Of Credit [Member]
Debt Instrument [Line Items]
Maximum outstanding balance	$ 179.3	$ 185.5
Average outstanding balance	73.3	102.7
Warehouse Facility II [Member]
Debt Instrument [Line Items]
Maximum outstanding balance	153.6	177.2
Average outstanding balance	90.0	158.9
Warehouse Facility III [Member]
Debt Instrument [Line Items]
Maximum outstanding balance		73.0
Average outstanding balance		67.3
Warehouse Facility IV [Member]
Debt Instrument [Line Items]
Maximum outstanding balance	39.6	39.6
Average outstanding balance	$ 37.7	$ 37.9