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Long-Term Borrowings and Subordinated Debt - Narrative (Details) | Dec. 31, 2023 USD ($) privatePlacement | Dec. 31, 2022 USD ($)
--- | --- | ---
Debt Instrument [Line Items] |  |
Long-term borrowings at FHLB | $ 39,300,000 | $ 14,700,000
Loans pledged as collateral at FHLB | 4,600,000,000 |
Maximum eligible borrowing based on qualifying collateral at FHLB | 2,700,000,000 |
Maximum borrowing capacity at FHLB | $ 3,200,000,000 |
Number of completed private placements of trust preferred securities | privatePlacement | 3 |
DNB Capital Trust I | Junior subordinated debt |  |
Debt Instrument [Line Items] |  |
Debt instrument, face amount | $ 5,000,000 |
Carrying amount of equity component | $ 200,000 |
Trusts |  |
Debt Instrument [Line Items] |  |
Percentage of equity owned | 100.00% |

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