Loans and the Allowance for Loan Losses - Additional Information (Detail) $ in Millions	Sep. 30, 2015 USD ($)
American Gateway Financial Corporation [Member]
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities Acquired During Period [Line Items]
Performing loans	$ 142.8

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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