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v3.24.0.1

Investments (Additional Information) (Details) - USD ($) | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Jun. 30, 2022 | Dec. 31, 2023 | Dec. 31, 2022 | Jan. 01, 2020
Schedule of Investments [Line Items] |  |  |  |
Trading securities |  | $ 4,647,000 | $ 3,990,000 |
AFS debt securities, allowance |  | 0 | 0 | $ 0
Net unrealized loss on debt securities, net of tax |  | (60,500,000) | 79,400,000 |
Deferred Tax Assets, Unrealized Losses on Available-for-Sale Securities, Gross |  |  | 21,700,000 |
Deferred Tax Liabilities, Investments |  | 16,600,000 |  |
Debt Securities, Held-to-Maturity, Excluded Accrued Interest from Amortized Cost |  | 1,700,000 |  |
Security Owned And Pledged As Collateral Amortized Cost |  | 675,500,000 | 821,900,000 |
Debt Securities, Held-to-Maturity, Credit Loss Expense (Reversal) |  | 1,838,000 | 0 |
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Writeoff |  | (1,838,000) | 0 |
Proceeds, Debt Securities, Held-to-Maturity, Previously Written off, Recovery |  | 910,000 |  |
Asset Pledged as Collateral |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Debt Securities, Available-for-Sale and Held-to-Maturity, Fair Value |  | 607,900,000 | 726,500,000 |
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 |  | 46,900,000 |  |
Deferred Tax Assets, Unrealized Losses on Available-for-Sale Securities, Gross |  | 12,800,000 |  |
Available-for-sale Securities |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Interest Receivable |  | 1,700,000 | $ 1,900,000 |
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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