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Description of Business (Percentage of Consumer Loans Assigned with FICO Score of Less Than 650 or No FICO Score) (Details)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Percentage Of Contracts With FICO Score Lower Than 650 Or No FICO Score [Member]
Financing Receivable, Recorded Investment [Line Items]
Percentage of total unit volume with FICO score lower than 650 o no FICO score	0.966	0.963

X

- Definition

Includes any additional disclosures related to the credit quality of financing receivables. This may include a description of a credit quality indicator or a description of how the internal risk ratings used by a company relate to the likelihood of loss.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 29
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953659-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 30
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953664-111524

+ Details

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X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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Namespace Prefix:
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