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Fair Value of Financial Instruments - Narrative (Details) - USD ($) | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Feb. 28, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Non-marketable equity securities held in other financial institutions |  |  |  | $ 55,190,000 | $ 67,378,000 |
Impairment recorded on investments in equity securities that do not have readily determinable fair values |  |  |  | 0 |  |
Change in fair value of equity investments |  |  |  | 10,096,000 | 0 | $ 19,000
Liability to repurchase past due GNMA loans | $ 24,600,000 |  |  | 0 | 24,600,000 |
Settlement of sale of GNMA MSR | $ 1,800,000 | $ 1,800,000 | $ 1,800,000 | 1,806,000 | 0 | $ 0
Loan balance individually evaluated |  |  |  | 5,011,000 | 8,217,000 |
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Nonrecurring |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Loan balance individually evaluated |  |  |  | 19,700,000 | 20,700,000 |
Foreclosed assets |  |  |  | 3,900,000 | 806,000 |
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Nonrecurring | Residential real estate | Real estate |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Residential mortgage loans in the process of foreclosure |  |  |  | $ 0 | $ 10,000 |
Minimum | Measurement Input, Credit Spread |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Credit spread, securities at fair value through income |  |  |  | 0.83% | 0.83% |
Maximum | Measurement Input, Credit Spread |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Credit spread, securities at fair value through income |  |  |  | 2.27% | 2.27% |

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