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Summary of Significant Accounting Policies $ / shares in Units, $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 USD ($) $ / shares | Mar. 31, 2020 segment | Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) $ / shares | Sep. 30, 2019 USD ($) | Dec. 31, 2019 USD ($)
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Number of reportable segments | segment |  |  | 1 |  |  |  |
Uninsured cash and cash equivalents |  | $ 8.5 |  |  | $ 8.5 |  | $ 186.1
Adoption of CECL | [1] |  |  |  | 0.0 |  |
Provision for credit losses |  | (29.8) |  | $ 19.3 | 464.3 | $ 49.2 |
CECL Impact on Net Income |  | $ 87.9 |  |  | $ 328.2 |  |
CECL Impact on Net Income, Per Diluted Share | $ / shares |  | $ 4.92 |  |  | $ 18.26 |  |
Restricted Cash and Cash Equivalents [Member] |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Uninsured cash and cash equivalents |  | $ 388.1 |  |  | $ 388.1 |  | $ 326.7
New Consumer Loan Assignments [Member] |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Provision for credit losses |  | 114.1 |  | 0.0 | 426.2 | 0.0 |
Loans Receivable [Member] |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Adoption of CECL | [1] |  |  |  | 2,463.6 |  |
Provision for credit losses |  | $ 0.0 |  | $ 0.0 | $ 0.0 | $ 0.0 |
[1] | Represents the gross-up of Loans receivable and allowance for credit losses on January 1, 2020 upon the adoption of CECL for the present value of the difference between contractual future net cash flows and expected future net cash flows discounted at the effective interest rate.

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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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