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Summary of Significant Accounting Policies (Narrative) (Details) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2019 USD ($) segment portfolio_segment | Dec. 31, 2018 USD ($)
Summary Of Significant Accounting Policies [Line Items] |  |
Document Period End Date | Sep. 30, 2019 |
Number of reportable segments | segment | 1 |
Uninsured cash and cash equivalents | $ 24.0 | $ 25.1
Number of portfolio segments | portfolio_segment | 2 |
Period after Consumer Loan assignment that Dealer Loans written off | 120 months |
Period after month of purchase that Purchased Loans written off | 120 months |
Right-of-use asset | $ 3.0 |
Lease liability | 3.2 |
Restricted Cash and Cash Equivalents [Member] |  |
Summary Of Significant Accounting Policies [Line Items] |  |
Uninsured cash and cash equivalents | $ 326.5 | $ 303.0

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- Definition The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD. + References No definition available. + Details
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
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