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Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2024 USD ($) | Jun. 30, 2024 segment office | Jun. 02, 2003 shares
Financing Receivable, Past Due [Line Items] |  |  |
Bank common stock exchanged for company common stock (in shares) | shares |  |  | 1
Number of branch offices | office |  | 7 |
Number of reportable segments | segment |  | 1 |
MHC |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Allowance for credit loss, increase (decrease) | $ (5.8) |  |
C&I |  |  |
Financing Receivable, Past Due [Line Items] |  |  |
Allowance for credit loss, increase (decrease) | $ 4.6 |  |

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