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v3.25.0.1

Investments (Additional Information) (Details) - USD ($) | 1 Months Ended | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jun. 30, 2022 | Mar. 31, 2023 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Schedule of Investments [Line Items] |  |  |  |  |
Trading securities |  |  | $ 5,243,000 | $ 4,647,000 |
AFS debt securities, allowance |  |  | 0 | 0 |
Net unrealized loss on debt securities, net of tax |  |  | 62,200,000 | 60,500,000 |
Deferred Tax Assets, Unrealized Losses on Available-for-Sale Securities, Gross |  |  |  | 16,600,000 |
Deferred Tax Liabilities, Investments |  |  | 17,000,000.0 |  |
Debt Securities, Held-to-Maturity, Excluded Accrued Interest from Amortized Cost |  |  | 1,600,000 | 1,700,000 | $ 0
Security Owned And Pledged As Collateral Amortized Cost |  |  | 519,900,000 | 675,500,000 |
Debt Securities, Held-to-Maturity, Credit Loss Expense (Reversal) |  | $ 1,800,000 | (910,000) | 1,838,000 |
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Writeoff |  |  | 0 | (1,838,000) |
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Recovery |  |  | 910,000 | 0 |
Asset Pledged as Collateral |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
Debt Securities, Available-for-Sale and Held-to-Maturity, Fair Value |  |  | 449,000,000.0 | 607,900,000 |
Transferred Securities |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
AFS debt securities, fair value, transfer amount | $ 520,300,000 |  |  |  |
AFS debt securities, transfer, unrealized loss | $ 72,100,000 |  |  |  |
Net unrealized loss on debt securities, net of tax |  |  | 41,800,000 | 46,900,000 |
Deferred Tax Assets, Unrealized Losses on Available-for-Sale Securities, Gross |  |  | 11,400,000 | 12,800,000 |
Available-for-sale Securities |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
Interest Receivable |  |  | $ 1,700,000 | $ 1,700,000 |
Signature Bank Corporate Bond |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Writeoff |  | $ 8,000 |  |  |

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