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Fair Values of Assets and Liabilities - Schedule of Assets Measured on Non-Recurring Basis (Detail) - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total Assets | $ 1,118,163 | $ 938,309
Fair Value, Nonrecurring [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | 47,274 | 49,147
Other real estate owned | 1,063 | 1,319
Total Assets | 48,337 | 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 | 1,109,483 | 930,020
Level 2 [Member] | Fair Value, Nonrecurring [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | 29,467 | 35,543
Other real estate owned | 1,063 | 1,319
Total Assets | 30,530 | 36,862
Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total Assets | 8,680 | 8,289
Level 3 [Member] | Fair Value, Nonrecurring [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | 17,807 | 13,604
Other real estate owned | 0 | 0
Total Assets | $ 17,807 | $ 13,604

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