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, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	$ 200.1		$ 181.7		$ 195.4		$ 176.4
Provision for credit losses	4.6		5.4		9.3		11.2
Write-offs	(0.4)		(2.0)		(0.9)		(3.1)
Recoveries	0.5	[1]	0.7	[1]	1.0	[1]	1.3	[1]
Balance, end of period	204.8		185.8		204.8		185.8
Dealer Loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	190.8		172.9		185.7		167.4
Provision for credit losses	4.9		3.9		10.0		9.9
Write-offs	(0.4)		(1.9)		(0.9)		(3.0)
Recoveries	0.5	[1]	0.6	[1]	1.0	[1]	1.2	[1]
Balance, end of period	195.8		175.5		195.8		175.5
Purchased Loans [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Balance, beginning of period	9.3		8.8		9.7		9.0
Provision for credit losses	(0.3)		1.5		(0.7)		1.3
Write-offs	0		(0.1)		0		(0.1)
Recoveries	0	[1]	0.1	[1]	0	[1]	0.1	[1]
Balance, end of period	$ 9.0		$ 10.3		$ 9.0		$ 10.3

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