Loans - Restructured in Troubled Debt (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) loan	Dec. 31, 2017 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	25	20
Loan Balance	$ 14,626	$ 17,303
Specific Reserve	$ 4,554	$ 5,689
Commercial, industrial, and agricultural
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	10	11
Loan Balance	$ 4,577	$ 5,213
Specific Reserve	$ 104	$ 245
Commercial mortgages
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	15	9
Loan Balance	$ 10,049	$ 12,090
Specific Reserve	$ 4,450	$ 5,444
Residential real estate
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	0	0
Loan Balance	$ 0	$ 0
Specific Reserve	$ 0	$ 0
Consumer
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	0	0
Loan Balance	$ 0	$ 0
Specific Reserve	$ 0	$ 0
Credit cards
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	0	0
Loan Balance	$ 0	$ 0
Specific Reserve	$ 0	$ 0

Financing receivable modifications specific reserve.

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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

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

+ Details

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- Definition

The amount of the outstanding recorded investment related to 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 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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