Loans and Allowance for Loan Losses - Schedule of Troubled Debt Restructurings by Class of Loans (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) Loan
Financing Receivable Impaired [Line Items]
Trouble debt restructurings, Number of loans \| Loan	2
Trouble debt restructurings, Recorded investment	$ 15,508
Trouble debt restructurings, Impairment recognized	$ 4,994
Commercial Real Estate [Member]
Financing Receivable Impaired [Line Items]
Trouble debt restructurings, Number of loans \| Loan	1
Trouble debt restructurings, Recorded investment	$ 1,247
Commercial and Industrial [Member]
Financing Receivable Impaired [Line Items]
Trouble debt restructurings, Number of loans \| Loan	1
Trouble debt restructurings, Recorded investment	$ 14,261
Trouble debt restructurings, Impairment recognized	$ 4,994

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18845-111554

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Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18845-111554

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