Detail of Troubled Debt Restructurings (Detail) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015 USD ($) Loans	Sep. 30, 2015 USD ($) Loans
Financing Receivable, Modifications [Line Items]
Outstanding Recorded Investment Pre-Modification	$ 269	$ 269
Outstanding Recorded Investment Post-Modification	$ 268	$ 267
Number of Loans	1	1
Interest Income Recognized	$ 3	$ 3
Commercial installment
Financing Receivable, Modifications [Line Items]
Outstanding Recorded Investment Pre-Modification	0	0
Outstanding Recorded Investment Post-Modification	$ 0	$ 0
Number of Loans \| Loans	0	0
Interest Income Recognized	$ 0	$ 0
Commercial real estate
Financing Receivable, Modifications [Line Items]
Outstanding Recorded Investment Pre-Modification	269	269
Outstanding Recorded Investment Post-Modification	$ 268	$ 267
Number of Loans	1	1
Interest Income Recognized	$ 3	$ 3
Consumer real estate
Financing Receivable, Modifications [Line Items]
Outstanding Recorded Investment Pre-Modification	0	0
Outstanding Recorded Investment Post-Modification	$ 0	$ 0
Number of Loans	0	0
Interest Income Recognized	$ 0	$ 0
Consumer installment
Financing Receivable, Modifications [Line Items]
Outstanding Recorded Investment Pre-Modification	0	0
Outstanding Recorded Investment Post-Modification	$ 0	$ 0
Number of Loans	0	0
Interest Income Recognized	$ 0	$ 0

Financing Receivable, Modifications, Number of Contracts, During Period

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Financing Receivable, Modifications, Post-Modification Recorded Investment During Period

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Financing Receivable, Modifications, Pre-Modification Recorded Investment During Period

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Amount of interest income recognized, modified by troubled debt restructurings.

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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.

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