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Fair Value Measurements - Narrative (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading investments | $ 54,481 | $ 55,903
Vertical risk retention, amount | $ 54,000 | $ 51,000
Vertical risk retention interest | 5.00% | 5.00%
Gain (loss) debt securities | $ 3,000 | $ (1,000)
Gain (loss) on investment | 4,000 | 13,000
Debt Securities, Trading |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Settlement debt securities | 1,000 | 13,000
Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading investments | $ 54,000 | $ 56,000
Minimum | Measurement Input CPR Rate |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Measurement input | 0.081 |
Minimum | Measurement Input, Default Rate |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Measurement input |  | 0.051
Maximum | Measurement Input CPR Rate |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Measurement input | 0.122 |
Maximum | Measurement Input, Default Rate |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Measurement input |  | 0.207
Weighted Average | Measurement Input CPR Rate |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Measurement input | 0.0949 |
Weighted Average | Measurement Input, Default Rate |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Measurement input |  | 0.1103
Convertible Debt Securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading investments |  | $ 5,000
Interest income, debt securities, trading | $ 1,000 | $ 1,000

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