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Loans Receivable Loans Receivable (Summary of Provision for Credit Losses) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | $ (8.3) | $ (29.8) | $ (17.5) | $ 464.3
Dealer Loans [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | (9.5) | (26.4) | (36.8) | 202.8
Purchased Loans [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | 1.2 | (3.4) | 19.3 | 261.5
New Consumer Loan Assignments [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | 75.5 | 114.1 | 298.9 | 426.2
New Consumer Loan Assignments [Member] | Dealer Loans [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | 32.0 | 45.6 | 123.2 | 171.3
New Consumer Loan Assignments [Member] | Purchased Loans [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | 43.5 | 68.5 | 175.7 | 254.9
Forecast Changes [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | (83.8) | (143.9) | (316.4) | 38.1
Forecast Changes [Member] | Dealer Loans [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | (41.5) | (72.0) | (160.0) | 31.5
Forecast Changes [Member] | Purchased Loans [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Provision for credit losses | $ (42.3) | $ (71.9) | $ (156.4) | $ 6.6

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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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