Branch Acquisition - Additional Information (Detail) - Retail Branch [Member]	Mar. 11, 2016 USD ($)
Business Acquisition [Line Items]
Deposit premium	$ 340,000
Percentage of core deposits	2.50%
Percentage of deposit premium, contingent on the core deposit	1.00%

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.

Name:	us-gaap_BusinessAcquisitionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration