Loans - Restructured in Troubled Debt (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) loan	Dec. 31, 2018 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	23	25
Loan Balance	$ 9,802	$ 14,626
Specific Reserve	$ 358	$ 4,554
Commercial, industrial, and agricultural
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	10	10
Loan Balance	$ 3,093	$ 4,577
Specific Reserve	$ 28	$ 104
Commercial mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	13	15
Loan Balance	$ 6,709	$ 10,049
Specific Reserve	$ 330	$ 4,450
Residential real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0	0
Loan Balance	$ 0	$ 0
Specific Reserve	$ 0	$ 0
Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0	0
Loan Balance	$ 0	$ 0
Specific Reserve	$ 0	$ 0
Credit cards
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans \| loan	0	0
Loan Balance	$ 0	$ 0
Specific Reserve	$ 0	$ 0

Financing receivable modifications specific reserve.

No definition available.

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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

+ References

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- Definition

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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