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Leases - Additional Information (Detail) |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Jun. 11, 2024 USD ($) Property | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) Number | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($)
Lessee Lease Description [Line Items] |  |  |  |  |  |
Loss on disposition of equipment |  |  |  |  | $ 2,522,000 |
Future lease payments |  | $ 9,185,000 |  | $ 9,185,000 |  |
Finance lease liability |  | 1,467,000 |  | 1,467,000 |  | $ 1,509,000
Operating lease, Right-of-use asset |  | 5,426,000 |  | 5,426,000 |  | 5,648,000
Operating lease liability |  | 5,426,000 |  | $ 5,426,000 |  | $ 5,648,000
Branch Office and Certain Equipment Expires in June 2039 |  |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |  |
Lease expiration month and year |  |  |  | 2039-06 |  |
Future lease payments |  | 8,700,000 |  | $ 8,700,000 |  |
Finance lease liability |  | 1,500,000 |  | 1,500,000 |  |
Sale-leaseback transaction resulted pre-tax gain |  |  |  |  | 2,500,000 |
Operating lease expense |  | 164,000 | $ 131,000 | $ 528,000 | 160,000 |
Leased ATMs Expires in August 2030 |  |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |  |
Lease expiration month and year |  |  |  | 2030-08 |  |
Future lease payments |  | 374,000 |  | $ 374,000 |  |
Operating lease expense |  | 19,000 | 19,000 | $ 57,000 | 57,000 |
Branch Office Expires in August 2027 |  |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |  |
Lease expiration month and year |  |  |  | 2027-08 |  |
Future lease payments |  | 83,000 |  | $ 83,000 |  |
Operating lease expense |  | $ 10,000 | $ 10,000 | $ 30,000 | $ 29,000 |
Real estate and equipment [Member] | Maximum [Member] |  |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |  |
Operating leases remaining lease terms |  | 15 years |  | 15 years |  |
Office and Branch [Member] |  |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |  |
Aggregate cash purchase price | $ 7,500,000 |  |  |  |  |
Number of properties owned and operated | Property | 4 |  |  |  |  |
Number of lease renewal | Number |  |  |  | 1 |  |
Branch Office and Certain Equipment [Member] |  |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |  |
Operating lease, renewal term |  | 15 years |  | 15 years |  |
Operating lease initial term |  |  |  | 15 years |  |
Annual rent escalation percentage |  |  |  | 2.50% |  |

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