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Stockholders' Equity - Additional Information (Detail) - USD ($) | Jun. 30, 2021 | Jun. 17, 2021
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Subordinated Notes due 2036 [Member] | Private Placement [Member] |  |
Stockholders Equity [Line Items] |  |
Aggregate principal amount |  | $ 60,000,000
Small Business Administration (SBA), CARES Act, Paycheck Protection Program Lending Facility [Member] |  |
Stockholders Equity [Line Items] |  |
Percentage of risk weight under risk based capital rules | 0.00% |
Maximum [Member] |  |
Stockholders Equity [Line Items] |  |
Quantitative limit for trust preferred securities to be included in tier 1 capital | $ 15,000,000,000 |

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