Loans Receivable (Summary Of Changes In Allowance For Credit Losses) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Jun. 30, 2013		Jun. 30, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance, beginning of period	$ 181.7		$ 159.4		$ 176.4		$ 154.3
Provision for credit losses	5.4		2.8		11.2		8.0
Write-offs	(2.0)		(0.8)		(3.1)		(1.5)
Recoveries	0.7	[1]	0.5	[1]	1.3	[1]	1.1	[1]
Balance, end of period	185.8		161.9		185.8		161.9
Dealer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance, beginning of period	172.9		148.3		167.4		141.7
Provision for credit losses	3.9		3.6		9.9		10.2
Write-offs	(1.9)		(0.4)		(3.0)		(1.0)
Recoveries	0.6	[1]	0.5	[1]	1.2	[1]	1.1	[1]
Balance, end of period	175.5		152.0		175.5		152.0
Purchased Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance, beginning of period	8.8		11.1		9.0		12.6
Provision for credit losses	1.5		(0.8)		1.3		(2.2)
Write-offs	(0.1)		(0.4)		(0.1)		(0.5)
Recoveries	0.1	[1]			0.1	[1]
Balance, end of period	$ 10.3		$ 9.9		$ 10.3		$ 9.9

[1] Represents collections received on previously written off Loans.