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Loans Receivable Loans Receivable (Summary of Provision for Credit Losses) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | $ 139.4 | $ 15.4 | $ 494.1 | $ 29.9
Dealer Loans [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | 61.1 | 14.5 | 229.2 | 26.1
Purchased Loans [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | 78.3 | 0.9 | 264.9 | 3.8
New Consumer Loan Assignments [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | 154.2 | 0.0 | 312.1 | 0.0
New Consumer Loan Assignments [Member] | Dealer Loans [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | 60.9 | 0.0 | 125.7 | 0.0
New Consumer Loan Assignments [Member] | Purchased Loans [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | 93.3 | $ 0.0 | 186.4 | $ 0.0
Forecast Changes [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | (14.8) |  | 182.0 |
Forecast Changes [Member] | Dealer Loans [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | 0.2 |  | 103.5 |
Forecast Changes [Member] | Purchased Loans [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | $ (15.0) |  | $ 78.5 |

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- Definition Amount of expense related to estimated loss from loan and lease transactions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.11) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 + Details
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