Loans - Troubled Debt Restructurings Segregated by Class (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) Loan	Dec. 31, 2017 USD ($) Loan	Dec. 31, 2016 USD ($) Loan	Dec. 31, 2015 USD ($) Loan
Financing Receivable, Modifications [Line Items]
Number of Loans \| Loan	3	3	3	3
Post-Modification Outstanding Recorded Investment		$ 3,047	$ 3,288	$ 3,858
Real Estate Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| Loan	3	3
Pre-Modification Outstanding Recorded Investment	$ 4,871	$ 4,871
Post-Modification Outstanding Recorded Investment	$ 2,782	$ 3,047
Commercial Real Estate Portfolio Segment [Member] \| Real Estate Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| Loan	3	3
Pre-Modification Outstanding Recorded Investment	$ 4,871	$ 4,871
Post-Modification Outstanding Recorded Investment	$ 2,782	$ 3,047

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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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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