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Fair Values of Assets and Liabilities - Schedule of Assets Measured on Non-Recurring Basis (Detail) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total Assets | $ 1,206,844 | $ 938,309
Fair Value, Nonrecurring [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | 37,106 | 49,147
Other real estate owned | 631 | 1,319
Total Assets | 37,737 | 50,466
Level 1 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total Assets | 0 | 0
Level 1 [Member] | Fair Value, Nonrecurring [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | 0 | 0
Other real estate owned | 0 | 0
Total Assets | 0 | 0
Level 2 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total Assets | 1,190,561 | 930,020
Level 2 [Member] | Fair Value, Nonrecurring [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | 24,512 | 35,543
Other real estate owned | 631 | 1,319
Total Assets | 25,143 | 36,862
Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total Assets | 16,283 | 8,289
Level 3 [Member] | Fair Value, Nonrecurring [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | 12,594 | 13,604
Other real estate owned | 0 | 0
Total Assets | $ 12,594 | $ 13,604

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