Loans Receivable (Summary Of Changes In Allowance For Credit Losses) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Allowance, Beginning Balance	$ 154.3		$ 126.9		$ 117.6
Provision for credit losses	24.0		29.0		10.0
Write-offs	(4.2)		(3.5)		(3.1)
Recoveries	2.3	[1]	1.9	[1]	2.4	[1]
Loans and Leases Receivable, Allowance, Ending Balance	176.4		154.3		126.9
Dealer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Allowance, Beginning Balance	141.7		113.2		108.8
Provision for credit losses	27.1		29.7		5.1
Write-offs	(3.6)		(3.0)		(3.0)
Recoveries	2.2	[1]	1.8	[1]	2.3	[1]
Loans and Leases Receivable, Allowance, Ending Balance	167.4		141.7		113.2
Purchased Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Receivable, Allowance, Beginning Balance	12.6		13.7		8.8
Provision for credit losses	(3.1)		(0.7)		4.9
Write-offs	(0.6)		(0.5)		(0.1)
Recoveries	0.1	[1]	0.1	[1]	0.1	[1]
Loans and Leases Receivable, Allowance, Ending Balance	$ 9.0		$ 12.6		$ 13.7

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