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Loans Receivable (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Transfers | [1] |  | $ 0.0 | $ 0.0 | $ 0.0
Transfers | [2] |  | $ 0.0 | 0.0 |
Age of Consumer Loans contractual payments due with no forecasted future net cash flows |  |  | 120 months |  |
Impact of Forecast Change on Credit Losses |  |  | $ 41.6 |  |
Impact of Forecast Change on Finance Charges |  |  | 7.3 |  |
Impact of Forecast Change on Net Income |  |  | 30.8 |  |
Decrease in Forecated Net Cash Flows |  |  |  | 1.8 |
Dealer Loans [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Transfers | [1] | $ (89.0) | (78.2) | (93.1) | (10.1)
Transfers | [2] | $ (31.8) | (13.7) | (31.8) |
Purchased Loans [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Transfers | [1] |  | 78.2 | 93.1 | $ 10.1
Transfers | [2] |  | $ 13.7 | $ 31.8 |
[1] | Under our Portfolio Program, certain events may result in Dealers forfeiting their rights to Dealer Holdback. We transfer the Dealer’s outstanding Dealer Loan balance to Purchased Loans in the period this forfeiture occurs.
[2] | Under our Portfolio Program, certain events may result in Dealers forfeiting their rights to Dealer Holdback. We transfer the Dealer’s outstanding Dealer Loan balance to Purchased Loans in the period this forfeiture occurs. Beginning in the fourth quarter of 2017, we also transfer the related allowance for credit losses balance to Purchased Loans in the period this forfeiture occurs.

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- Definition Amount of other addition (reduction) in allowance reserve for credit 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 15 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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