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Loans Receivable (Schedule of Consumer Loans Forecasted Collection Percentage) (Details) | Mar. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
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Loans Originating In 2015 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1] | 65.30% |  | 65.20% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1] |  |  |  |  |  |  |  |  |  |  | 67.70%
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.10% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | (2.40%) |  |  |  |  |  |  |  |  |  |
Loans Originating In 2016 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1] | 63.80% |  | 63.80% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1] |  |  |  |  |  |  |  |  |  | 65.40% |
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.00% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | (1.60%) |  |  |  |  |  |  |  |  |  |
Loans Originating In 2017 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1] | 64.70% |  | 64.70% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1] |  |  |  |  |  |  |  |  | 64.00% |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.00% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 0.70% |  |  |  |  |  |  |  |  |  |
Loans Originating In 2018 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1] | 65.50% |  | 65.50% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1] |  |  |  |  |  |  |  | 63.60% |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.00% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 1.90% |  |  |  |  |  |  |  |  |  |
Loans Originating In 2019 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1] | 67.00% |  | 66.90% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1] |  |  |  |  |  |  | 64.00% |  |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.10% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 3.00% |  |  |  |  |  |  |  |  |  |
Loans Originating In 2020 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1] | 67.70% |  | 67.60% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1] |  |  |  |  |  | 63.40% |  |  |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.10% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 4.30% |  |  |  |  |  |  |  |  |  |
Loans Originating In 2021 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1] | 64.30% |  | 64.50% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1] |  |  |  |  | 66.30% |  |  |  |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | (0.20%) |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | (2.00%) |  |  |  |  |  |  |  |  |  |
Loans Originating In 2022 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1] | 62.10% |  | 62.70% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1] |  |  |  | 67.50% |  |  |  |  |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | (0.60%) |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | (5.40%) |  |  |  |  |  |  |  |  |  |
Loans Originating In 2023 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1] | 67.20% |  | 67.40% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1] |  |  | 67.50% |  |  |  |  |  |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | (0.20%) |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | (0.30%) |  |  |  |  |  |  |  |  |  |
Loans Originating In 2024 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1] | 66.90% |  |  |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1] | 66.90% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 0.00% |  |  |  |  |  |  |  |  |  |
Dealer Loans [Member] | Loans Originating In 2015 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 64.60% |  | 64.60% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  |  |  |  |  |  |  |  |  | 67.50%
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.00% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | (2.90%) |  |  |  |  |  |  |  |  |  |
Dealer Loans [Member] | Loans Originating In 2016 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 63.00% |  | 63.00% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  |  |  |  |  |  |  |  | 65.10% |
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.00% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | (2.10%) |  |  |  |  |  |  |  |  |  |
Dealer Loans [Member] | Loans Originating In 2017 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 64.00% |  | 64.00% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  |  |  |  |  |  |  | 63.80% |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.00% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 0.20% |  |  |  |  |  |  |  |  |  |
Dealer Loans [Member] | Loans Originating In 2018 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 64.90% |  | 64.90% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  |  |  |  |  |  | 63.60% |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.00% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 1.30% |  |  |  |  |  |  |  |  |  |
Dealer Loans [Member] | Loans Originating In 2019 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 66.70% |  | 66.50% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  |  |  |  |  | 63.90% |  |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.20% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 2.80% |  |  |  |  |  |  |  |  |  |
Dealer Loans [Member] | Loans Originating In 2020 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 67.50% |  | 67.40% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  |  |  |  | 63.30% |  |  |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.10% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 4.20% |  |  |  |  |  |  |  |  |  |
Dealer Loans [Member] | Loans Originating In 2021 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 64.10% |  | 64.20% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  |  |  | 66.30% |  |  |  |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | (0.10%) |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | (2.20%) |  |  |  |  |  |  |  |  |  |
Dealer Loans [Member] | Loans Originating In 2022 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 61.40% |  | 62.00% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  |  | 67.30% |  |  |  |  |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | (0.60%) |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | (5.90%) |  |  |  |  |  |  |  |  |  |
Dealer Loans [Member] | Loans Originating In 2023 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 66.10% |  | 66.40% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  | 66.80% |  |  |  |  |  |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | (0.30%) |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | (0.70%) |  |  |  |  |  |  |  |  |  |
Dealer Loans [Member] | Loans Originating In 2024 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 66.00% |  |  |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] | 66.00% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 0.00% |  |  |  |  |  |  |  |  |  |
Purchased Loans [Member] | Loans Originating In 2015 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 68.90% |  | 68.90% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  |  |  |  |  |  |  |  |  | 68.50%
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.00% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 0.40% |  |  |  |  |  |  |  |  |  |
Purchased Loans [Member] | Loans Originating In 2016 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 66.10% |  | 66.10% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  |  |  |  |  |  |  |  | 66.50% |
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.00% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | (0.40%) |  |  |  |  |  |  |  |  |  |
Purchased Loans [Member] | Loans Originating In 2017 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 66.30% |  | 66.30% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  |  |  |  |  |  |  | 64.60% |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.00% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 1.70% |  |  |  |  |  |  |  |  |  |
Purchased Loans [Member] | Loans Originating In 2018 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 66.80% |  | 66.80% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  |  |  |  |  |  | 63.50% |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.00% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 3.30% |  |  |  |  |  |  |  |  |  |
Purchased Loans [Member] | Loans Originating In 2019 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 67.70% |  | 67.50% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  |  |  |  |  | 64.20% |  |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.20% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 3.50% |  |  |  |  |  |  |  |  |  |
Purchased Loans [Member] | Loans Originating In 2020 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 67.90% |  | 67.80% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  |  |  |  | 63.60% |  |  |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | 0.10% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 4.30% |  |  |  |  |  |  |  |  |  |
Purchased Loans [Member] | Loans Originating In 2021 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 64.80% |  | 65.00% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  |  |  | 66.30% |  |  |  |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | (0.20%) |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | (1.50%) |  |  |  |  |  |  |  |  |  |
Purchased Loans [Member] | Loans Originating In 2022 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 63.80% |  | 64.30% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  |  | 68.00% |  |  |  |  |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | (0.50%) |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | (4.20%) |  |  |  |  |  |  |  |  |  |
Purchased Loans [Member] | Loans Originating In 2023 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage |  | 70.00% | [1],[2] | 70.10% |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] |  |  | 69.40% |  |  |  |  |  |  |  |
Variance In Forecasted Collection Percentage From Prior Year End |  | (0.10%) |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 0.60% |  |  |  |  |  |  |  |  |  |
Purchased Loans [Member] | Loans Originating In 2024 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Forecasted Collection Percentage | [1],[2] | 70.00% |  |  |  |  |  |  |  |  |  |
Initial Forecasted Collection Percentage | [1],[2] | 69.90% |  |  |  |  |  |  |  |  |  |
Variance In Initial Forecasted Collection Percentage |  | 0.10% |  |  |  |  |  |  |  |  |  |
[1] | Represents the total forecasted collections we expect to collect on the Consumer Loans as a percentage of the repayments that we were contractually owed on the Consumer Loans at the time of assignment. Contractual repayments include both principal and interest. Forecasted collection rates are negatively impacted by canceled Consumer Loans as the contractual amount owed is not removed from the denominator for purposes of computing forecasted collection rates in the table.
[2] | The forecasted collection rates presented for Dealer Loans and Purchased Loans reflect the Consumer Loan classification at the time of assignment.

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