Financial Instruments with Off-Balance-Sheet Risk - Additional Information (Detail) $ in Millions	Dec. 31, 2015 USD ($)
Commitments to Extend Credit [Member]
Other Commitments [Line Items]
Off balance sheet risk financial instruments	$ 176.8
Standby and commercial Letters of Credit [Member]
Other Commitments [Line Items]
Off balance sheet risk financial instruments	$ 9.2

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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