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Significant Accounting Policies - Additional Information (Details) | 12 Months Ended
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Dec. 31, 2025 USD ($) Fee RevenueCategory | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
Summary Of Significant Accounting Policies [Line Items] |  |  |
Percentage of outstanding principal to be repurchased under GNMA optional repurchase program | 100.00% |  |
Number of days to pass to be classified as past due LHFI | 30 days |  |
Finite-lived intangible assets, average useful life | 20 years |  |
Securities with limited marketability | $ 42,000,000 | $ 44,900,000 |
Other-than-temporary impairment of investment in member bank stock | $ 0 | 0 | $ 0
Number of types of interchange fees | Fee | 2 |  |
Other real estate sales, net (losses) gains | $ (1,759,000) | $ (1,104,000) | $ (145,000)
Number of trust management revenue categories | RevenueCategory | 4 |  |
Time period between service obligation completed and payment received from trust customer | 30 days |  |
Credit Card Loans [Member] |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Number of days past due loans are to be charged-off | 180 days |  |
Commercial Credits [Member] |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Number of days past due for loan to be classified as nonaccrual | 90 days |  |
Non-Business Purpose Credits [Member] |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Number of days past due for loan to be classified as nonaccrual | 120 days |  |
Number of days past due loans are to be charged-off | 120 days |  |
Minimum [Member] |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Number of days mortgage LHFS are retained on balance sheet | 30 days |  |
Minimum [Member] | Furniture and Equipment [Member] |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives of the assets | 3 years |  |
Maximum [Member] |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Number of days mortgage LHFS are retained on balance sheet | 45 days |  |
Maximum [Member] | Buildings [Member] |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives of the assets | 39 years |  |
Maximum [Member] | Furniture and Equipment [Member] |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives of the assets | 10 years |  |
Maximum [Member] | 1-4 Family Residential Real Estate [Member] |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Number of days past due loans are to be charged-off | 180 days |  |
ASU 2016-13 [Member] | Securities Available for Sale [Member] |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Current expected credit loss | $ 0 |  |

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