Loans Receivable (Summary Of Changes In Allowance For Credit Losses) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance, beginning of period	$ 195.4		$ 176.4		$ 154.3
Provision for credit losses	12.8		21.9		24.0
Write-offs	(3.2)		(5.3)		(4.2)
Recoveries	1.9	[1]	2.4	[1]	2.3	[1]
Balance, end of period	206.9		195.4		176.4
Dealer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance, beginning of period	185.7		167.4		141.7
Provision for credit losses	13.7		21.3		27.1
Write-offs	(3.1)		(5.2)		(3.6)
Recoveries	1.8	[1]	2.2	[1]	2.2	[1]
Balance, end of period	198.1		185.7		167.4
Purchased Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance, beginning of period	9.7		9.0		12.6
Provision for credit losses	(0.9)		0.6		(3.1)
Write-offs	(0.1)		(0.1)		(0.6)
Recoveries	0.1	[1]	0.2	[1]	0.1	[1]
Balance, end of period	$ 8.8		$ 9.7		$ 9.0

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