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Fair Value of Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2020 | Dec. 31, 2019 | Sep. 30, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Interest-bearing deposits maturing date | 90 days |  |
Collateral dependent impaired loans categorized as Level 3 | $ 15,259 | $ 3,061 | $ 3,228
Specific allocation for collateral dependent impaired loans | 1,198 | 197 | $ 187
Collateral Dependent [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Specific allocation for collateral dependent impaired loans | 1,200 | 197 |
Level 3 [Member] | Collateral Dependent [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Collateral dependent impaired loans categorized as Level 3 | $ 8,100 | $ 444 |

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