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Acquisition - Additional Information (Detail) - Apr. 17, 2015 | USD ($) Branches
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Business Acquisition [Line Items] |
Cash paid for deposits, premises and equipment | $ 6,618,000
Amount for acquisition of premises and equipment | 4,495,000
Total deposits liabilities assumed | 186,819,000
Bank Of America [Member] |
Business Acquisition [Line Items] |
Amount for acquisition of premises and equipment | 2,165,000
Total deposits liabilities assumed | 186,136,000
Loans acquired | $ 0
Bank Of America [Member] | Virginia [Member] |
Business Acquisition [Line Items] |
Number of acquired branches | Branches | 6

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