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Loans - Narrative (Details) - USD ($) |  |  |  | 12 Months Ended
--- | --- | --- | --- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Aug. 01, 2022 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
PCD loans | $ 34,800,000 | $ 48,100,000 |  |  |  |
Accrued interest | 35,100,000 | 27,100,000 |  | $ 35,100,000 | $ 27,100,000 |
Declined amount of provision expense for loan credit losses |  |  |  | 4,100,000 |  |
Provision expense for loan credit losses |  |  |  | 17,514,000 | 21,613,000 | $ (10,798,000)
Collectively evaluated portion of increase (decrease) related to reserve | 5,300,000 |  |  | 5,300,000 |  |
Individually evaluated portion of increase (decrease) related to reserve | 4,400,000 |  |  | 4,400,000 |  |
Funding commitments | 1,600,000 | 0 |  | 1,600,000 | 0 |
Gross interest income that would have been recorded |  |  |  | 12,049,000 | 8,759,000 | 12,234,000
Transfer from held for sale portfolio to held for investment portfolio |  |  |  | 7,100,000 |  |
Nonaccrual mortgage loans held for sale recorded at fair value | $ 0 | $ 3,900,000 |  | 0 | 3,900,000 |
BTH |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
PCD loans |  |  | $ 47,127,000 |  |  |
CECL loan provision |  |  | $ 14,900,000 |  |  |
Nonperforming Financial Instruments |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Gross interest income that would have been recorded |  |  |  | 1,400,000 | 1,300,000 | 1,900,000
Interest income |  |  |  | $ 0 | $ 0 | $ 0

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