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Summary of Significant Accounting Policies (Narrative) (Details) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Mar. 31, 2020 USD ($) | Mar. 31, 2019 USD ($) | Sep. 30, 2019 segment | Dec. 31, 2019 USD ($)
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Adoption of CECL | [1] | $ 0 |  |  |
Provision for credit losses |  | 354,700,000 | $ 14,500,000 |  |
Number of reportable segments | segment |  |  |  | 1 |
Uninsured cash and cash equivalents |  | 25,100,000 |  |  | $ 186,100,000
CECL Impact on Net Income |  | 121,600,000 |  |  |
CECL Impact on Net Income, Per Diluted Share |  | 6.69 |  |  |
Restricted Cash and Cash Equivalents [Member] |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Uninsured cash and cash equivalents |  | 404,300,000 |  |  | $ 326,700,000
New Consumer Loan Assignments [Member] |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Provision for credit losses |  | 157,900,000 |  |  |
Loans Receivable [Member] |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |
Adoption of CECL | [1] | 2,463,600,000 |  |  |
Provision for credit losses |  | $ 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 CECL Impact on Net Income, Per Diluted Share + References No definition available. + Details
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- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599 + Details
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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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