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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

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-Subparagraph (SX 210.9-03.7(d))

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-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Subparagraph d

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-Name Accounting Standards Codification

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-Section 50

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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Loans Receivable (Schedule Of Consumer Loans Performance) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 2,719.8				$ 2,408.2				$ 2,109.9	$ 1,752.9
Allowance for credit losses	(206.9)				(195.4)				(176.4)	(154.3)
Loans receivable, net	2,512.9	2,407.4	2,358.0	2,318.0	2,212.8	2,163.4	2,092.7	2,028.6
Loan Pool Performance Meets Or Exceeds Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	1,262.8				908.7
Allowance for credit losses	0				0
Loans receivable, net	1,262.8				908.7
Loan Pool Performance Less Than Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	1,457.0				1,499.5
Allowance for credit losses	(206.9)				(195.4)
Loans receivable, net	1,250.1				1,304.1
Dealer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	2,389.8				2,155.5				1,869.4	1,506.5
Allowance for credit losses	(198.1)				(185.7)				(167.4)	(141.7)
Loans receivable, net	2,191.7				1,969.8
Dealer Loans [Member] \| Loan Pool Performance Meets Or Exceeds Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	945.1				681.4
Allowance for credit losses	0				0
Loans receivable, net	945.1				681.4
Dealer Loans [Member] \| Loan Pool Performance Less Than Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	1,444.7				1,474.1
Allowance for credit losses	(198.1)				(185.7)
Loans receivable, net	1,246.6				1,288.4
Purchased Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	330.0				252.7				240.5	246.4
Allowance for credit losses	(8.8)				(9.7)				(9.0)	(12.6)
Loans receivable, net	321.2				243.0
Purchased Loans [Member] \| Loan Pool Performance Meets Or Exceeds Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	317.7				227.3
Allowance for credit losses	0				0
Loans receivable, net	317.7				227.3
Purchased Loans [Member] \| Loan Pool Performance Less Than Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	12.3				25.4
Allowance for credit losses	(8.8)				(9.7)
Loans receivable, net	$ 3.5				$ 15.7