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Stockholders' Equity - Additional Information (Detail) - USD ($) | Jan. 01, 2020 | Jun. 30, 2020
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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%
ASU No. 2016-13 [Member] |  |
Stockholders Equity [Line Items] |  |
Increase to retained earnings for cumulative effect of adopting ASU | $ 2,300,000 |
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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- Definition Quantitative limit for trust preferred securities to be included in tier one capital. + References No definition available. + Details
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- Definition Amount of the cumulative effect on retained earnings net of related income tax effect. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22663-107794 + Details
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