Loans Receivable (Summary Of Changes In Allowance For Credit Losses) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance, beginning of period		$ 206.9	$ 195.4	$ 176.4
Provision for credit losses		41.5	12.8	21.9
Write-offs		(6.6)	(3.2)	(5.3)
Recoveries	[1],[2]	1.8	1.9	2.4
Balance, end of period		243.6	206.9	195.4
Dealer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance, beginning of period		198.1	185.7	167.4
Provision for credit losses		41.8	13.7	21.3
Write-offs		(6.4)	(3.1)	(5.2)
Recoveries	[1],[2]	1.6	1.8	2.2
Balance, end of period		235.1	198.1	185.7
Purchased Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance, beginning of period		8.8	9.7	9.0
Provision for credit losses		(0.3)	(0.9)	0.6
Write-offs		(0.2)	(0.1)	(0.1)
Recoveries	[1],[2]	0.2	0.1	0.2
Balance, end of period		$ 8.5	$ 8.8	$ 9.7

[1] Represents collections received on previously written off Loans

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