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Fair Value Measurements - Schedule of Fair Value Measurements (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | $ 435,559 | $ 553,554 |
Equity securities with readily determinable fair values | 888 | 1,719 | $ 2,609
Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 0 | 0 |
Equity securities with readily determinable fair values | 888 | 1,719 |
Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 435,559 | 553,554 |
Equity securities with readily determinable fair values | 0 | 0 |
Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 0 | 0 |
Equity securities with readily determinable fair values | 0 | 0 |
U.S. Government and agencies |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 196,775 | 210,999 |
Mortgage-backed securities |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 223,725 | 295,718 |
State and municipal |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale |  | 15,235 |
Corporate bonds |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 15,059 | 31,602 |
Recurring | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 0 | 0 |
Equity securities with readily determinable fair values | 888 | 1,719 |
Recurring | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 435,559 | 553,554 |
Equity securities with readily determinable fair values | 0 | 0 |
Recurring | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 0 | 0 |
Equity securities with readily determinable fair values | 0 | 0 |
Recurring | U.S. Government and agencies | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 0 | 0 |
Recurring | U.S. Government and agencies | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 196,775 | 210,999 |
Recurring | U.S. Government and agencies | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 0 | 0 |
Recurring | Mortgage-backed securities | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 0 | 0 |
Recurring | Mortgage-backed securities | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 223,725 | 295,718 |
Recurring | Mortgage-backed securities | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 0 | 0 |
Recurring | State and municipal | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale |  | 0 |
Recurring | State and municipal | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale |  | 15,235 |
Recurring | State and municipal | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale |  | 0 |
Recurring | Corporate bonds | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 0 | 0 |
Recurring | Corporate bonds | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 15,059 | 31,602 |
Recurring | Corporate bonds | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 0 | 0 |
Nonrecurring | Individually evaluated loans | Level 1 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Impaired loans | 0 | 0 |
Nonrecurring | Individually evaluated loans | Level 2 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Impaired loans | 0 | 0 |
Nonrecurring | Individually evaluated loans | Level 3 |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Impaired loans | 242 | 3,773 |
Fair Value |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 435,559 | 553,554 |
Equity securities with readily determinable fair values | 888 | 1,719 |
Fair Value | Recurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 435,559 | 553,554 |
Equity securities with readily determinable fair values | 888 | 1,719 |
Fair Value | Recurring | U.S. Government and agencies |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 196,775 | 210,999 |
Fair Value | Recurring | Mortgage-backed securities |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 223,725 | 295,718 |
Fair Value | Recurring | State and municipal |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale |  | 15,235 |
Fair Value | Recurring | Corporate bonds |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Debt securities available for sale | 15,059 | 31,602 |
Fair Value | Nonrecurring | Individually evaluated loans |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Impaired loans | $ 242 | $ 3,773 |

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