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Stockholders' Equity - Additional Information (Detail) - USD ($)	Jan. 01, 2020	Jun. 30, 2020
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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+ References

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- Definition

Quantitative limit for trust preferred securities to be included in tier one capital.

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- Definition

Stockholders equity.

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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

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