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Loans - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2024 | Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Fair value adjustment of derivative | $ 969 | $ 2,700
Asset Pledged as Collateral without Right [Member] | HELOC [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Residential mortgage loan | 11,600 | 12,100
Asset Pledged as Collateral without Right [Member] | Commercial Real Estate [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Residential mortgage loan | 364,200 | 158,900
Asset Pledged as Collateral without Right [Member] | Residential Mortgage [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Residential mortgage loan | $ 204,800 | $ 210,900

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