Loans and Other Real Estate - Summary of Restructured Loans (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) Contract	Mar. 31, 2018 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	0	2
Pre- Modification Outstanding Recorded Investment	$ 0	$ 1,657
Post- Modification Outstanding Recorded Investment	$ 0	$ 1,657
Commercial, secured by real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| Contract	0	2
Pre- Modification Outstanding Recorded Investment	$ 0	$ 1,657
Post- Modification Outstanding Recorded Investment	$ 0	$ 1,657

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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