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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

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5074-111524

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-Name Accounting Standards Codification

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-Paragraph 2

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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-Name Accounting Standards Codification

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Loans Receivable (Schedule of Consumer Loans Performance) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	$ 2,562.8	$ 2,518.1	$ 2,408.2	$ 2,278.5	$ 2,210.3	$ 2,109.9
Allowance for credit losses	(204.8)	(200.1)	(195.4)	(185.8)	(181.7)	(176.4)
Loans receivable, net	2,358.0		2,212.8
Loan Pool Performance Meets Or Exceeds Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	958.3		908.7
Allowance for credit losses
Loans receivable, net	958.3		908.7
Loan Pool Performance Less Than Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	1,604.5		1,499.5
Allowance for credit losses	(204.8)		(195.4)
Loans receivable, net	1,399.7		1,304.1
Dealer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	2,279.0	2,247.0	2,155.5	2,041.4	1,973.1	1,869.4
Allowance for credit losses	(195.8)	(190.8)	(185.7)	(175.5)	(172.9)	(167.4)
Loans receivable, net	2,083.2		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	715.9		681.4
Allowance for credit losses
Loans receivable, net	715.9		681.4
Dealer Loans [Member] \| Loan Pool Performance Less Than Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	1,563.1		1,474.1
Allowance for credit losses	(195.8)		(185.7)
Loans receivable, net	1,367.3		1,288.4
Purchased Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	283.8	271.1	252.7	237.1	237.2	240.5
Allowance for credit losses	(9.0)	(9.3)	(9.7)	(10.3)	(8.8)	(9.0)
Loans receivable, net	274.8		243.0
Purchased Loans [Member] \| Loan Pool Performance Meets Or Exceeds Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	242.4		227.3
Allowance for credit losses
Loans receivable, net	242.4		227.3
Purchased Loans [Member] \| Loan Pool Performance Less Than Initial Estimates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable	41.4		25.4
Allowance for credit losses	(9.0)		(9.7)
Loans receivable, net	$ 32.4		$ 15.7