Non Purchased Loans - Changes in Troubled Debt Restructurings (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) Loan	Dec. 31, 2018 USD ($) Loan	Dec. 31, 2017 USD ($) Loan
Receivables [Abstract]
Number of Loans \| Loan	3	3	3
Additional loans with concessions, Recorded Investment	$ 2,495
Principal paydowns, Recorded Investment	(287)	$ (265)	$ (241)
Post-Modification Outstanding Recorded Investment	$ 2,782	$ 3,047	$ 3,288

Financing Receivable, Modifications, Collections During Period

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- Definition

Financing Receivable, Modifications, Recorded Investment During Period

+ References

No definition available.

+ Details

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- Definition

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

+ 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

+ Details

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- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

+ Details

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- References

No definition available.

+ Details

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